For many years, UNAIDS and the rest of the HIV industry have been sending out the message that everyone is at risk of being infected with HIV. However, it has never been true that everyone is at risk and there was never any reason for claiming this. The fact that HIV tended to cluster in urban areas, among wealthier, more mobile and better educated populations has been clear for a long time.
One of the latest papers to include detailed spacial data which demonstrates this clustering effect is entitled 'Localized spatial clustering of HIV infections in a widely disseminated rural South African epidemic', by Frank Tanser and colleagues. The data they produce is very interesting, but the same can certainly not be said of the conclusions they draw.
Unsurprisingly, they assume throughout that HIV is almost always transmitted through heterosexual sex in African countries, the so called 'behavioral paradigm'. And the study is in South Africa, the country with the largest number of people living with HIV in the world. As usual, the assumption is unexamined and unsupported in any way.
The study finds that high HIV prevalence clusters close to the National Road and that it is far lower in inaccessible rural areas. 40% of infected people live within 1km of the National Road. Also the "estimated density of HIV-infected individuals (total HIV cases per square kilometre) living within 1km of the road is 15.7 times higher than the mean density of infected individuals across the remainder of the study area."
Those infected are also better educated, wealthier and far more likely to be employed. No surprises there. And they are also less likely to be migrants. Migrants, especially internal migrants, are one of the groups often said to be at high risk of being infected and of infecting others. But the HIV industry has always been bad at identifying risk groups or, I should say, good at ignoring any evidence that may help identify them.
Whatever theories the paper's authors may have, indeed, whatever prejudices, all this data supports the view that HIV is not entirely spread sexually. The populations in this and other studies also have something else in common: they all live close to or have easy access to health facilities. Wealthy, well educated, mobile people with jobs tend to go to health facilities.
On the other hand, rural people tend to go to health facilities far less often, for various reasons, including poverty, lack of mobility, lack of health related education and the sheer lack of decent, affordable, accessible health facilities. Do these features of serious underdevelopment give people protection from HIV infection? Well, that's a hard question to answer if researchers like Tanser and colleagues don't even raise it.
The authors speculate about why the factors that may have been significant in HIV transmission during an early phase of the epidemic appear to be significant still and why this apparently heterosexually transmitted virus has not been more evenly spread among the population. Just how many warning signs do they need that their overall hypothesis about the virus being spread almost entirely through heterosexual sex is wrong and is little more than an anti-African prejudice?
As if things are not bad enough, this sort of idle speculation and pig-headed refusal to consider some fairly obvious alternatives to the behavioral paradigm is going to encourage those baying for 'treatment as prevention' and pre-exposure prophylaxis (essentially, means of substantially increasing the tonnage of drugs being thrown at the epidemic) to be rolled out in high prevalence countries.
Showing posts with label mathematical models. Show all posts
Showing posts with label mathematical models. Show all posts
Sunday, July 24, 2011
Monday, July 18, 2011
The Sound of a One Legged Argument Kicking Itself
As I mentioned in yesterday's blog, a recent article finds evidence for the concurrency hypothesis 'compelling', despite liberal use of words that suggests a lot of doubt. The hypothesis is that lots of unsafe sex alone, involving numerous partners, low condom use, etc, does not account for high HIV prevalence; but if sexual relationships overlap with each other, HIV transmission will be very high.
A lot of work has been done to show that the concurrency hypothesis is entirely unsupported by evidence, particularly work by Eileen Stillwaggon and Larry Sawers. But in the article mentioned yesterday, Mah and Shelton dismiss anything challenging the hypothesis rather than addressing the failure of all the arguments that claim to support it.
Well, an article just published by Frank Tanser and colleagues finds that there is "no evidence to suggest that concurrent partnerships are an important driver of HIV incidence in [a] typical high-prevalence rural African population." But instead they argue that multiple partnerships are an important driver of incidence.
While Mah and Shelton denied that non-sexually transmitted HIV plays an important role in hyperendemic scenarios, without arguing the case, Tanser and colleagues don't even mention the possibility of non-sexual transmission. While obligingly neutralizing an argument that should never have been given much credence, and one that has been convincingly refuted by others, they seem to be taking a step backwards.
We have been hearing the oversexed African hypothesis for several decades now, it even predates the identification of HIV. So all Tanser has done is revived that tired old reflex as an explanation of massive rates of HIV transmission. But what is it about Africans that results in a virus that is difficult to transmit sexually spreading so fast in a population in which sexual behavior is little different from that found in many other low HIV prevalence populations?
Rates of new infections per year for both males and females in the study population are shockingly high But the researchers don't appear to have established how HIV was being transmitted. They have just assumed that transmission is all through heterosexual sex and then attempted to work out how risky heterosexual sex is among participants. But why is heterosexual sex so risky there? We are not told.
The authors find that "More than 24% of the adult population are infected with HIV and infection peaks at more than 50% in women aged 25–29 years and 44% in men aged 30–34 years." Given the fairly low probability of sexual transmission of HIV, 80 or 90% of women must be exposed to HIV if such high percentages end up infected.
The fact that male prevalence peaks in an older age group than female prevalence is sometimes explained by the 'fact' that older men have younger partners. But only some men have younger partners. Some have partners the same age as themselves. Like a lot of HIV related data, you could be forgiven for thinking that HIV in males is a different virus from HIV in females.
Despite flogging the dead horse of concurrency, which is worthwhile when you consider how much credence it still seems to have in the HIV industry, the authors remark that concurrency may have played a big part in earlier stages in high prevalence epidemics. But earlier treatment of the concurrency hypothesis suggest otherwise, so this concession doesn't exactly strengthen their argument for a return to the promiscuity theory of HIV.
And when it comes to their recommendations for HIV prevention strategy they really seem to weaken. They argue that 'messages' shouldn't be 'diluted'. Pumping out a fairly undiluted though highly stigmatizing message about HIV for many years has not resulted in UNAIDS having much success in reducing transmission, despite spending billions. In fact, the pharmaceutical lobby trying to increase drug use in the pretence that it will reduce transmission even refers to the institution's prevention work as a failure.
Telling people the truth about HIV transmission is not 'diluting' anything. If people are at risk they need to know about the risks and how to avoid them. UNAIDS have used the issue of 'dilution' as a reason for denying non-sexual risks, with the result that most people don't know that such risks exist, and therefore cannot avoid them. HIV prevention is not just an advertising campaign, even if it's never looked much different from one.
A lot of work has been done to show that the concurrency hypothesis is entirely unsupported by evidence, particularly work by Eileen Stillwaggon and Larry Sawers. But in the article mentioned yesterday, Mah and Shelton dismiss anything challenging the hypothesis rather than addressing the failure of all the arguments that claim to support it.
Well, an article just published by Frank Tanser and colleagues finds that there is "no evidence to suggest that concurrent partnerships are an important driver of HIV incidence in [a] typical high-prevalence rural African population." But instead they argue that multiple partnerships are an important driver of incidence.
While Mah and Shelton denied that non-sexually transmitted HIV plays an important role in hyperendemic scenarios, without arguing the case, Tanser and colleagues don't even mention the possibility of non-sexual transmission. While obligingly neutralizing an argument that should never have been given much credence, and one that has been convincingly refuted by others, they seem to be taking a step backwards.
We have been hearing the oversexed African hypothesis for several decades now, it even predates the identification of HIV. So all Tanser has done is revived that tired old reflex as an explanation of massive rates of HIV transmission. But what is it about Africans that results in a virus that is difficult to transmit sexually spreading so fast in a population in which sexual behavior is little different from that found in many other low HIV prevalence populations?
Rates of new infections per year for both males and females in the study population are shockingly high But the researchers don't appear to have established how HIV was being transmitted. They have just assumed that transmission is all through heterosexual sex and then attempted to work out how risky heterosexual sex is among participants. But why is heterosexual sex so risky there? We are not told.
The authors find that "More than 24% of the adult population are infected with HIV and infection peaks at more than 50% in women aged 25–29 years and 44% in men aged 30–34 years." Given the fairly low probability of sexual transmission of HIV, 80 or 90% of women must be exposed to HIV if such high percentages end up infected.
The fact that male prevalence peaks in an older age group than female prevalence is sometimes explained by the 'fact' that older men have younger partners. But only some men have younger partners. Some have partners the same age as themselves. Like a lot of HIV related data, you could be forgiven for thinking that HIV in males is a different virus from HIV in females.
Despite flogging the dead horse of concurrency, which is worthwhile when you consider how much credence it still seems to have in the HIV industry, the authors remark that concurrency may have played a big part in earlier stages in high prevalence epidemics. But earlier treatment of the concurrency hypothesis suggest otherwise, so this concession doesn't exactly strengthen their argument for a return to the promiscuity theory of HIV.
And when it comes to their recommendations for HIV prevention strategy they really seem to weaken. They argue that 'messages' shouldn't be 'diluted'. Pumping out a fairly undiluted though highly stigmatizing message about HIV for many years has not resulted in UNAIDS having much success in reducing transmission, despite spending billions. In fact, the pharmaceutical lobby trying to increase drug use in the pretence that it will reduce transmission even refers to the institution's prevention work as a failure.
Telling people the truth about HIV transmission is not 'diluting' anything. If people are at risk they need to know about the risks and how to avoid them. UNAIDS have used the issue of 'dilution' as a reason for denying non-sexual risks, with the result that most people don't know that such risks exist, and therefore cannot avoid them. HIV prevention is not just an advertising campaign, even if it's never looked much different from one.
Sunday, July 17, 2011
Concurrency Regurgitated: Dubious Evidence Found Increasingly Credible by Experts
For unbridled spite and anti-African prejudice, packed up in some academic sounding writing, it would be hard to beat Timothy Mah and James Shelton's 'Concurrency revisited: increasing and compelling epidemiological evidence'. Don't worry, it's not in the least bit compelling.
One of the main claims of the article is that the person engaging in concurrent relationships doesn't face as high a risk as all their partners. And this is supposed to explain why another study showed that, although men were five times more likely to report having concurrent relationships than women, women are far more likely to be HIV positive.
The gist of the pro-concurrency argument is that while multiple partnerships alone, even the sort of multiples estimated by those with similar prejudices to Mah and Shelton, do not explain extraordinarily high rates of transmission found in many epidemics, concurrency does explain them.
Concurrency is roughly defined as "overlapping sexual partnerships in which sexual intercourse with one partner occurs between two acts of intercourse with another partner". But because there is little useful evidence about rates of such behavior, in African countries or anywhere else, researchers usually resort to data which bears little application to that (or any other) definition of the word.
Authors promoting the concept as an explanation of high HIV prevalence claim that it is the only possible explanation. However it is not an explanation at all, even if you insist, as the HIV industry does, that HIV is almost always transmitted through heterosexual sex in African countries. It has never been demonstrated that concurrency levels are high where HIV transmission is high or that high levels of concurrency even result in high rates of transmission.
Mah and Shelton proceed to list various pieces of research that show that HIV is probably frequently transmitted non sexually; they just don't see the research as showing this. Earlier researchers 'presumed' that HIV transmission where only one partner in a relationship is infected occurred through extra-marital sex. They generally didn't check and when they did, they chose not to believe anything that didn't fit their prejudices.
People like Mah and Shelton could do with a bit of instruction in basic logic. If you assume the truth of your conclusion and use that as your premise, you will end up with a fallacy. Some of the researchers are even frank enough to use words like 'presume' and 'probably' in their cited remarks. But Mah and Shelton feign complete confidence in their conclusions, despite the high incidence of words like 'appear', 'suggest', 'likely', 'may', etc, throughout their paper.
A recent paper which shows prominent clusters of HIV prevalence around roads does not, as Mah and Shelton wish to suggest, support the concurrency hypothesis. But it is consistent with the hypothesis that infections cluster around health facilities and routes to and from health facilities. However, even after exposure to the many articles they cite in their bibliography, they still adhere to their half baked ideas, finding them "reasonable and salient".
Given their insistence that HIV is almost always transmitted through heterosexual sex in high prevalence countries (though nowhere else), the authors plump for male circumcision as the reason why HIV transmission rates in West Africa have always been far lower than in East and South African countries. This especially weak version of the highly questionable mass male circumcision drive taking place in East and South Africa is said to be 'plausible', which probably shows more about the minds (and scruples) of the proponents than anything else.
Just when you might have thought those tired old arguments had been put out to grass, along come Mah and Shelton to compound them with some even more clapped out considerations. In my next post I'll cover an article which shows that concurrency is not a significant driver of HIV transmission but that multiple partnerships are. And that old chestnut dates back to the days when even experts agreed that HIV wasn't always sexually transmitted. But that's how AIDS billions get spent.
One of the main claims of the article is that the person engaging in concurrent relationships doesn't face as high a risk as all their partners. And this is supposed to explain why another study showed that, although men were five times more likely to report having concurrent relationships than women, women are far more likely to be HIV positive.
The gist of the pro-concurrency argument is that while multiple partnerships alone, even the sort of multiples estimated by those with similar prejudices to Mah and Shelton, do not explain extraordinarily high rates of transmission found in many epidemics, concurrency does explain them.
Concurrency is roughly defined as "overlapping sexual partnerships in which sexual intercourse with one partner occurs between two acts of intercourse with another partner". But because there is little useful evidence about rates of such behavior, in African countries or anywhere else, researchers usually resort to data which bears little application to that (or any other) definition of the word.
Authors promoting the concept as an explanation of high HIV prevalence claim that it is the only possible explanation. However it is not an explanation at all, even if you insist, as the HIV industry does, that HIV is almost always transmitted through heterosexual sex in African countries. It has never been demonstrated that concurrency levels are high where HIV transmission is high or that high levels of concurrency even result in high rates of transmission.
Mah and Shelton proceed to list various pieces of research that show that HIV is probably frequently transmitted non sexually; they just don't see the research as showing this. Earlier researchers 'presumed' that HIV transmission where only one partner in a relationship is infected occurred through extra-marital sex. They generally didn't check and when they did, they chose not to believe anything that didn't fit their prejudices.
People like Mah and Shelton could do with a bit of instruction in basic logic. If you assume the truth of your conclusion and use that as your premise, you will end up with a fallacy. Some of the researchers are even frank enough to use words like 'presume' and 'probably' in their cited remarks. But Mah and Shelton feign complete confidence in their conclusions, despite the high incidence of words like 'appear', 'suggest', 'likely', 'may', etc, throughout their paper.
A recent paper which shows prominent clusters of HIV prevalence around roads does not, as Mah and Shelton wish to suggest, support the concurrency hypothesis. But it is consistent with the hypothesis that infections cluster around health facilities and routes to and from health facilities. However, even after exposure to the many articles they cite in their bibliography, they still adhere to their half baked ideas, finding them "reasonable and salient".
Given their insistence that HIV is almost always transmitted through heterosexual sex in high prevalence countries (though nowhere else), the authors plump for male circumcision as the reason why HIV transmission rates in West Africa have always been far lower than in East and South African countries. This especially weak version of the highly questionable mass male circumcision drive taking place in East and South Africa is said to be 'plausible', which probably shows more about the minds (and scruples) of the proponents than anything else.
Just when you might have thought those tired old arguments had been put out to grass, along come Mah and Shelton to compound them with some even more clapped out considerations. In my next post I'll cover an article which shows that concurrency is not a significant driver of HIV transmission but that multiple partnerships are. And that old chestnut dates back to the days when even experts agreed that HIV wasn't always sexually transmitted. But that's how AIDS billions get spent.
Saturday, July 16, 2011
Presentation at Kilimanjaro Clinical Research Institute
Hordes of articles are appearing right now about some promising results from the use of antiretroviral drugs (ARV) to prevent HIV, as opposed to treating it. This is called pre-exposure prophylaxis or PrEP. But the question is, who will benefit from this use of ARVs, which has mainly been tested on Africans?
ARVs are expensive, despite all the posturing about agreements and deals brokered by Bill Clinton and other notable self-publicists. They are so expensive that few countries with serious HIV epidemics and large scale treatment programs have ever been able to cover more than half of the HIV positive population, at most. Usually coverage is a lot less than half.
The biggest programs in East Africa only include a few hundred thousand people, out of millions infected. But HIV negative populations are many times larger than HIV positive populations. Over 90% of the populations in all the East African countries are HIV negative. How will people be selected for PrEP programs? According to the HIV industry most sexually active Africans are at risk of being infected.
Yesterday I had the pleasure of making a brief presentation about sexual and non-sexual HIV transmission to a group of people who work or study at the Kilimanjaro Clinical Research Institute, part of the Kilimanjaro Christian Medical Center (a powerpoint of the presentation slides is available on the KCRI site). The talk was about my usual concern, the 'behavioral paradigm'. This is the view that HIV is almost always transmitted through heterosexual sex in high prevalence African countries.
This 'paradigm' is not based on evidence. In fact, it is frequently contradicted, especially by UNAIDS's own data. But as the flagship of the AIDS industry, this means that resulting UN policy is almost entirely based on what amounts to an extremely racist view. How will that racism, which so far has resulted in a lot of money being spent on large-scale finger-wagging exercises, affect the rollout of PrEP?
One of the slides I used at the presentation was a screenshot of the mathematical model used to back up the industry's claim that most Africans are at risk of being infected with this difficult to transmit virus. The 'Modes of Transmission Survey' for Kenya, for example, suggests that 44% of the 1.5 million HIV positive people were infected by ordinary heterosexual sex. And members of other groups that would be considered to be at low risk in non-African countries are also mysteriously infected in huge numbers.
UNAIDS' argument for this is somewhat circular because the claim that members of the largest group of HIV positive people are infected by their regular partner is supported by the idea that most regular partners have, or at one time had, 'unsafe sex'. But these are just more assumptions based on the behavioral paradigm, not pieces of data that might support it.
It's hard to know whether this adherence to the behavioral paradigm is going to blow up in the industry's face, or whether it will just feed their ongoing demand for profits at any cost. If virtually every sexually active person in a population is at risk, will they all be offered PrEP? Or are UNAIDS going to claim that PrEP is not appropriate for groups that have been considered to be at high risk up to now?
There is also a problem right now about funding ARVs for people who would die without them. Who will stump up tens of times more funding for drugs for people who will not die without them, probably won't benefit from them at all and may even be harmed by them? If saving the lives of some HIV positive people is not considered worth the effort, is it worth the cost and effort to play around with the lives of huge numbers of people just so pharmaceutical companies can become even richer than they already are.
My worry is not just about the use of drugs to reduce HIV transmission. My worry is about the serious lack of clarity about why certain people, mostly Africans, are so susceptible to a virus that is difficult to transmit sexually, yet so many are infected. Simply throwing a lot of drugs at the problem is unlikely to make it go away. This problem needs to be explained without the use of the thoroughly discredited behavioral paradigm.
[For more about pre-exposure prophylaxis, see my other blog.]
ARVs are expensive, despite all the posturing about agreements and deals brokered by Bill Clinton and other notable self-publicists. They are so expensive that few countries with serious HIV epidemics and large scale treatment programs have ever been able to cover more than half of the HIV positive population, at most. Usually coverage is a lot less than half.
The biggest programs in East Africa only include a few hundred thousand people, out of millions infected. But HIV negative populations are many times larger than HIV positive populations. Over 90% of the populations in all the East African countries are HIV negative. How will people be selected for PrEP programs? According to the HIV industry most sexually active Africans are at risk of being infected.
Yesterday I had the pleasure of making a brief presentation about sexual and non-sexual HIV transmission to a group of people who work or study at the Kilimanjaro Clinical Research Institute, part of the Kilimanjaro Christian Medical Center (a powerpoint of the presentation slides is available on the KCRI site). The talk was about my usual concern, the 'behavioral paradigm'. This is the view that HIV is almost always transmitted through heterosexual sex in high prevalence African countries.
This 'paradigm' is not based on evidence. In fact, it is frequently contradicted, especially by UNAIDS's own data. But as the flagship of the AIDS industry, this means that resulting UN policy is almost entirely based on what amounts to an extremely racist view. How will that racism, which so far has resulted in a lot of money being spent on large-scale finger-wagging exercises, affect the rollout of PrEP?
One of the slides I used at the presentation was a screenshot of the mathematical model used to back up the industry's claim that most Africans are at risk of being infected with this difficult to transmit virus. The 'Modes of Transmission Survey' for Kenya, for example, suggests that 44% of the 1.5 million HIV positive people were infected by ordinary heterosexual sex. And members of other groups that would be considered to be at low risk in non-African countries are also mysteriously infected in huge numbers.
UNAIDS' argument for this is somewhat circular because the claim that members of the largest group of HIV positive people are infected by their regular partner is supported by the idea that most regular partners have, or at one time had, 'unsafe sex'. But these are just more assumptions based on the behavioral paradigm, not pieces of data that might support it.
It's hard to know whether this adherence to the behavioral paradigm is going to blow up in the industry's face, or whether it will just feed their ongoing demand for profits at any cost. If virtually every sexually active person in a population is at risk, will they all be offered PrEP? Or are UNAIDS going to claim that PrEP is not appropriate for groups that have been considered to be at high risk up to now?
There is also a problem right now about funding ARVs for people who would die without them. Who will stump up tens of times more funding for drugs for people who will not die without them, probably won't benefit from them at all and may even be harmed by them? If saving the lives of some HIV positive people is not considered worth the effort, is it worth the cost and effort to play around with the lives of huge numbers of people just so pharmaceutical companies can become even richer than they already are.
My worry is not just about the use of drugs to reduce HIV transmission. My worry is about the serious lack of clarity about why certain people, mostly Africans, are so susceptible to a virus that is difficult to transmit sexually, yet so many are infected. Simply throwing a lot of drugs at the problem is unlikely to make it go away. This problem needs to be explained without the use of the thoroughly discredited behavioral paradigm.
[For more about pre-exposure prophylaxis, see my other blog.]
Sunday, July 10, 2011
Mathematical Modelers: the Latter-Day Myth Makers
Although I'm not that comfortable with mathematical models, even I know that if you use obscene values you will get obscene results. So the model used by UNAIDS to persuade people that Africans have inordinate and unfeasible levels of unsafe sex is an interesting case in point.
Scratch the surface a little and you'll wonder whether UNAIDS is manned by robots, idiots or fascists (or perhaps all three are compatible). Almost everyone in the example population faces some kind of risk from HIV. And almost everyone is at relatively high risk of being infected sexually, even though sexual transmission is not very likely for the majority of people anywhere.
The most obscene figures, to my mind, are the ones for transmission through medical injections and blood transfusions. However you could argue that the most obscene figures are the ones that are not included at all, those for transmission through other healthcare risks, perhaps risks associated with traditional practices and with cosmetic practices, such as tattooing, hairdressing, manicure and pedicure.
Eva Deuchert and Stuart Brody published an article on mathematical models entitled 'Plausible and Implausible Parameters for Mathematical Modeling of Nominal Heterosexual HIV Transmission' in 2007. They warn that not all transmission is through heterosexual sex and that not all heterosexual sex is penile-vaginal; some is anal, which carries a much higher transmission risk.
The authors also mention the possibility that mathematical models can be intimidating to many readers, who may conclude that it's all so complicated that it must be true. But it is vital for anyone trying to understand how UNAIDS come up with such strange conclusions to spend a bit of time with the models. It is important to criticize the policies they so frequently claim resulted in reductions in HIV transmission and that these reductions were a direct effect of sexual behavior change.
Firstly, sexual behavior was not (or not wholly) responsible for the massive HIV epidemics experienced by a number of sub-Saharan African countries. And therefore, changes in sexual behavior could not have resulted in drops in prevalence. But secondly, far higher levels of 'unsafe' sexual behavior than have ever been identified (and probably higher than is possible for humans) would not result in the rates of HIV transmission found in the worst hit countries.
UNAIDS and others who believe their unwarranted assumptions about sexual transmission in (some parts of) Africa then need to impute all sorts of things to Africans in order to explain serious epidemics. They need to ignore any non-sexual risks and even the elevated risk from anal sex. And this means that, even if people wanted to avoid various risks, they wouldn't even know that what they were involved in was risky.
The authors also put their finger on an important reason why it only seems like sex workers face very high risks as a result of their sexual behavior: if they do have any symptoms that seem like sexually transmitted infections, they could face the higher risk of being 'treated' with unsafe infections. UNAIDS have never even acknowledge the mystery behind extremely high HIV rates among sex workers. It’s a mystery because HIV prevalence among sex workers in most countries is very low.
Similar remarks apply to truckers and all the other people who are said to be at high risk of HIV infection. If they are really as sexually active as they are said to be, they will probably be infected with a sexually transmitted infection, eventually. And then they face the even considerable risks that go with unsafe treatment. The rounding up of sex workers, truckers and other ‘risk groups’, especially in the 80s and 90s, may well have done as much to spread HIV as it did to persuade donors that their money was being well spent.
The public is so used to hearing about these strange Africans with their bizarre sexual behaviour, they don't even notice that they are being asked to believe that significant numbers of people have up to 47 sexual contacts per day, that 20% of unmarried women have 25 sexual contacts per month and that 2% of married women have 100 sexual contacts per month.
This crazy mathematical model that UNAIDS put so much faith in, along with a whole lot of other similarly crazy models, has very serious consequences. They are used to support HIV policies which achieve little but the reinforcement of stigmatizing attitudes. Those policies have not resulted in reducing HIV transmission and they never will. We need to look beyond the pompous tones, the pretty pictures and graphs and the impressive looking models and see UNAIDS policy documents for what they are: dangerous lies.
Scratch the surface a little and you'll wonder whether UNAIDS is manned by robots, idiots or fascists (or perhaps all three are compatible). Almost everyone in the example population faces some kind of risk from HIV. And almost everyone is at relatively high risk of being infected sexually, even though sexual transmission is not very likely for the majority of people anywhere.
The most obscene figures, to my mind, are the ones for transmission through medical injections and blood transfusions. However you could argue that the most obscene figures are the ones that are not included at all, those for transmission through other healthcare risks, perhaps risks associated with traditional practices and with cosmetic practices, such as tattooing, hairdressing, manicure and pedicure.
Eva Deuchert and Stuart Brody published an article on mathematical models entitled 'Plausible and Implausible Parameters for Mathematical Modeling of Nominal Heterosexual HIV Transmission' in 2007. They warn that not all transmission is through heterosexual sex and that not all heterosexual sex is penile-vaginal; some is anal, which carries a much higher transmission risk.
The authors also mention the possibility that mathematical models can be intimidating to many readers, who may conclude that it's all so complicated that it must be true. But it is vital for anyone trying to understand how UNAIDS come up with such strange conclusions to spend a bit of time with the models. It is important to criticize the policies they so frequently claim resulted in reductions in HIV transmission and that these reductions were a direct effect of sexual behavior change.
Firstly, sexual behavior was not (or not wholly) responsible for the massive HIV epidemics experienced by a number of sub-Saharan African countries. And therefore, changes in sexual behavior could not have resulted in drops in prevalence. But secondly, far higher levels of 'unsafe' sexual behavior than have ever been identified (and probably higher than is possible for humans) would not result in the rates of HIV transmission found in the worst hit countries.
UNAIDS and others who believe their unwarranted assumptions about sexual transmission in (some parts of) Africa then need to impute all sorts of things to Africans in order to explain serious epidemics. They need to ignore any non-sexual risks and even the elevated risk from anal sex. And this means that, even if people wanted to avoid various risks, they wouldn't even know that what they were involved in was risky.
The authors also put their finger on an important reason why it only seems like sex workers face very high risks as a result of their sexual behavior: if they do have any symptoms that seem like sexually transmitted infections, they could face the higher risk of being 'treated' with unsafe infections. UNAIDS have never even acknowledge the mystery behind extremely high HIV rates among sex workers. It’s a mystery because HIV prevalence among sex workers in most countries is very low.
Similar remarks apply to truckers and all the other people who are said to be at high risk of HIV infection. If they are really as sexually active as they are said to be, they will probably be infected with a sexually transmitted infection, eventually. And then they face the even considerable risks that go with unsafe treatment. The rounding up of sex workers, truckers and other ‘risk groups’, especially in the 80s and 90s, may well have done as much to spread HIV as it did to persuade donors that their money was being well spent.
The public is so used to hearing about these strange Africans with their bizarre sexual behaviour, they don't even notice that they are being asked to believe that significant numbers of people have up to 47 sexual contacts per day, that 20% of unmarried women have 25 sexual contacts per month and that 2% of married women have 100 sexual contacts per month.
This crazy mathematical model that UNAIDS put so much faith in, along with a whole lot of other similarly crazy models, has very serious consequences. They are used to support HIV policies which achieve little but the reinforcement of stigmatizing attitudes. Those policies have not resulted in reducing HIV transmission and they never will. We need to look beyond the pompous tones, the pretty pictures and graphs and the impressive looking models and see UNAIDS policy documents for what they are: dangerous lies.
Wednesday, June 22, 2011
Sometimes Targets of Prejudice Embrace that Very Prejudice Themselves
It's odd sometimes how the targets of a prejudice embrace that very prejudice themselves. UNAIDS' prejudice about HIV almost always being transmitted sexually in African countries is a case in point. Academic articles and press coverage alike, explicitly or tacitly, assume the truth of the prejudice. And people here say 'we' or 'Kenyans' or 'Africans' like sex, have a lot of sex or prefer 'unsafe' sex.
In an article about adult male circumcision in Uganda, carried out with the aim of reducing HIV transmission (from females to males), Robert Kalumba warns that many people, male and female, seem convinced that the operation protects everyone from both infection and transmission. This is not the case, although the warning is nothing new.
But he also claims that "Ugandans love sex a lot" and it's hard to know what that means, aside from being an echo of the oft expressed prejudice. HIV prevalence is low in some parts of Uganda, high in others, low in some demographic groups and high in others. Do all Ugandans love sex? More than non-Ugandans? What about in places where HIV prevalence is low? What about non-Ugandans among whom HIV prevalence is far higher than it is in Uganda, such as Swaziland?
Kalumba also embraces the reflex about HIV being related to 'ignorance', just as others say that HIV is 'driven' by poverty. Neither of these reflexes are borne out by the evidence. HIV rates in high (and medium) prevalence countries are, in general, higher among those who have a higher level of education and are wealthier. And the effect is usually stronger among women than men.
Of course, lack of education and poverty are undesirable. The continued appalling educational, health and economic circumstances in developing countries is repugnant; but not because of their relation or lack of relation to HIV prevalence. Rather, HIV is repugnant because it is a virulent disease, one that spreads most readily among people who already face many other problems, such as low levels of access to adequate health facilities.
What Kalumba should be asking about mass male circumcision campaigns is why so much money and attention is going towards an operation which will only benefit some people, all men, when so many others are in even greater need, more often women than men. In fact, any effect in the field may prove small or even negative.
The United Nations General Assembly Special Sitting (UNGASS) report for Uganda in 2009 also makes one wonder to what extent HIV is sexually transmitted. A quick look at their graphs for HIV on the one hand and other recognized sexually transmitted diseases on the other shows that infection patterns are completely different.
Many would suspect that HIV is only partly sexually transmitted. And if they do, they will recognize that circumcision and other measures that assume the truth of the above mentioned prejudice will never be enough on their own.
While he is at it, Kalumba and others could take a look at various data from the Ugandan Demographic and Health Survey, which show that the highest figures for 'unsafe' sexual behavior are those for men, whereas the highest figures for HIV are for women. If he looks at the Aids Indicator Survey, he will notice many other anomalies, such as the number of people who are infected with HIV when they have never had sex, rarely had sex, only had sex with their partner or rarely had 'unsafe' sex.
The fact that some of the richest and most powerful HIV related institutions agree that HIV is almost always sexually transmitted in Africans does not make it so. And people like Kalumba need to be able to spot a prejudice for what it is. Because if Africans don't reject the prejudice, policy for HIV 'prevention' in Africa will continue to fail. You can't eliminate non-sexual transmission of HIV by targeting people's sexual behavior, especially among those who are not even sexually active.
In an article about adult male circumcision in Uganda, carried out with the aim of reducing HIV transmission (from females to males), Robert Kalumba warns that many people, male and female, seem convinced that the operation protects everyone from both infection and transmission. This is not the case, although the warning is nothing new.
But he also claims that "Ugandans love sex a lot" and it's hard to know what that means, aside from being an echo of the oft expressed prejudice. HIV prevalence is low in some parts of Uganda, high in others, low in some demographic groups and high in others. Do all Ugandans love sex? More than non-Ugandans? What about in places where HIV prevalence is low? What about non-Ugandans among whom HIV prevalence is far higher than it is in Uganda, such as Swaziland?
Kalumba also embraces the reflex about HIV being related to 'ignorance', just as others say that HIV is 'driven' by poverty. Neither of these reflexes are borne out by the evidence. HIV rates in high (and medium) prevalence countries are, in general, higher among those who have a higher level of education and are wealthier. And the effect is usually stronger among women than men.
Of course, lack of education and poverty are undesirable. The continued appalling educational, health and economic circumstances in developing countries is repugnant; but not because of their relation or lack of relation to HIV prevalence. Rather, HIV is repugnant because it is a virulent disease, one that spreads most readily among people who already face many other problems, such as low levels of access to adequate health facilities.
What Kalumba should be asking about mass male circumcision campaigns is why so much money and attention is going towards an operation which will only benefit some people, all men, when so many others are in even greater need, more often women than men. In fact, any effect in the field may prove small or even negative.
The United Nations General Assembly Special Sitting (UNGASS) report for Uganda in 2009 also makes one wonder to what extent HIV is sexually transmitted. A quick look at their graphs for HIV on the one hand and other recognized sexually transmitted diseases on the other shows that infection patterns are completely different.
Many would suspect that HIV is only partly sexually transmitted. And if they do, they will recognize that circumcision and other measures that assume the truth of the above mentioned prejudice will never be enough on their own.
While he is at it, Kalumba and others could take a look at various data from the Ugandan Demographic and Health Survey, which show that the highest figures for 'unsafe' sexual behavior are those for men, whereas the highest figures for HIV are for women. If he looks at the Aids Indicator Survey, he will notice many other anomalies, such as the number of people who are infected with HIV when they have never had sex, rarely had sex, only had sex with their partner or rarely had 'unsafe' sex.
The fact that some of the richest and most powerful HIV related institutions agree that HIV is almost always sexually transmitted in Africans does not make it so. And people like Kalumba need to be able to spot a prejudice for what it is. Because if Africans don't reject the prejudice, policy for HIV 'prevention' in Africa will continue to fail. You can't eliminate non-sexual transmission of HIV by targeting people's sexual behavior, especially among those who are not even sexually active.
Tuesday, June 14, 2011
Reducing Maternal HIV: the Only Acceptable Way of Reducing Pediatric HIV
The received view of HIV in high prevalence countries, especially African countries, is that roughly 80% is transmitted through heterosexual sex and most of the remaining 20% is transmitted from mother to child. So it's not surprising that the HIV hierarchy should target mother to child transmission, or at least talk about doing so. Even if the 80% estimate is way out, a very large number of children are infected during pregnancy, delivery or shortly after birth.
While no one could object to aiming to eliminate mother to child transmission, some might wonder if any effort will be made to prevent HIV in pregnant women. That might seem stupidly obvious but I don't see attempts being made to establish why so many pregnant women become infected with HIV, especially late in their pregnancy, or even shortly after birth.
Of course, transmission of sexually transmitted infections (STI) occur as a result of unprotected sex, as does pregnancy. But many of the women infected with HIV are not also, or not as much infected with more common and easier to transmit STIs. http://www.plusnews.org/report.aspx?ReportID=92664 Perhaps more strikingly, many women who are infected with HIV don't have HIV positive partners. And in a lot of cases, there is no routine follow up and testing of partners in African countries, so we can't always even be sure.
Although there is always the assumption that women who are infected shortly before, during or after their pregnancy are infected by their partner as a result of unprotected sex, there is a good chance that many women are not being infected by their partner, nor even through unprotected sex. UNAIDS' insistance that 80% of transmission in African countries is through heterosexual sex is, after all, not based on evidence. It is, on the whole, an unsupported assumption.
Something even better than preventing mother to child transmission, then, is preventing HIV in mothers. And where sexual partners are not even HIV positive, there is good reason to establish just how women are infected, and then use the resulting data to adjust the 80% figure. HIV transmission through some unknown route is very unlikely to be prevented. And that makes prevention of mother to child transmission a lot more difficult to effect.
In countries such as Libya and Romania, where massive rates of HIV transmission were recognized (and acknowledged) to have occurred through unsafe medical practices, many of the children infected went on to infect their mothers through breastfeeding, as opposed to the other way around. But such modes of transmission need to be recognized (and adknowledged) before they will be investigated, let alone prevented.
Recognizing non-sexual transmission would have another benefit: it would reduce stigma. If HIV positive Africans are told that it is almost certain that they were infected sexually, they will be stigmatized. Especially if it turns out that their partner is not infected. Allowing the possibility that HIV can be transmitted in other ways, which it most certainly can, could save a lot of marriages and lives, even the lives of children at risk of becoming infected.
There is some recognition that the state of public health facilities has direct consequences for the health of the people using those facilities. A lack of drugs, equipment and trained personnel has a negative impact on goals such as reducing child and maternal mortality, HIV transmission, malaria and other diseases.
Apparently, drugs and equipment can be stolen or may never reach health facilities. Sometimes patients have to bring the latex gloves and other equipment that will be used for their care. Perhaps sometimes equipment in short supply is reused, even without proper sterilization. But accepting that it can happen is not enough. It also needs to be established if this is contributing to transmission of diseases, such as HIV, and if so, how big this contribution is.
It's all very well to talk/write about destigmatization. But many of those doing the talking/writing are also doing the stigmatizing. There is plenty of evidence that HIV is not always transmitted sexually in Africa and there is evidence that possible cases of non-sexual transmission need to be investigated. Admitting this would go a long way towards reducing transmission, and also reducing stigmatization.
You will no more reduce stigmatization by saying 'stigma is bad' than you will influence sexual behavior by saying 'unprotected sex is risky'. We have learned that through many years of failing to have much impact on HIV transmission. The issue of stigma is very much in the hands of the people who warn us about how damaging it is, the UN, UNAIDS, WHO, CDC, the World Bank, etc.
The best way to reduce HIV transmission is to be clear about how the virus is being transmitted and not to depend on out of date and inappropriate figures. The best way to reduce mother to child transmission is to reduce the number of mothers being infected. And the best way to reduce stigma is to be honest about HIV transmission: we know that it is not always transmitted sexually and we don't even know how much is transmitted sexually.
While no one could object to aiming to eliminate mother to child transmission, some might wonder if any effort will be made to prevent HIV in pregnant women. That might seem stupidly obvious but I don't see attempts being made to establish why so many pregnant women become infected with HIV, especially late in their pregnancy, or even shortly after birth.
Of course, transmission of sexually transmitted infections (STI) occur as a result of unprotected sex, as does pregnancy. But many of the women infected with HIV are not also, or not as much infected with more common and easier to transmit STIs. http://www.plusnews.org/report.aspx?ReportID=92664 Perhaps more strikingly, many women who are infected with HIV don't have HIV positive partners. And in a lot of cases, there is no routine follow up and testing of partners in African countries, so we can't always even be sure.
Although there is always the assumption that women who are infected shortly before, during or after their pregnancy are infected by their partner as a result of unprotected sex, there is a good chance that many women are not being infected by their partner, nor even through unprotected sex. UNAIDS' insistance that 80% of transmission in African countries is through heterosexual sex is, after all, not based on evidence. It is, on the whole, an unsupported assumption.
Something even better than preventing mother to child transmission, then, is preventing HIV in mothers. And where sexual partners are not even HIV positive, there is good reason to establish just how women are infected, and then use the resulting data to adjust the 80% figure. HIV transmission through some unknown route is very unlikely to be prevented. And that makes prevention of mother to child transmission a lot more difficult to effect.
In countries such as Libya and Romania, where massive rates of HIV transmission were recognized (and acknowledged) to have occurred through unsafe medical practices, many of the children infected went on to infect their mothers through breastfeeding, as opposed to the other way around. But such modes of transmission need to be recognized (and adknowledged) before they will be investigated, let alone prevented.
Recognizing non-sexual transmission would have another benefit: it would reduce stigma. If HIV positive Africans are told that it is almost certain that they were infected sexually, they will be stigmatized. Especially if it turns out that their partner is not infected. Allowing the possibility that HIV can be transmitted in other ways, which it most certainly can, could save a lot of marriages and lives, even the lives of children at risk of becoming infected.
There is some recognition that the state of public health facilities has direct consequences for the health of the people using those facilities. A lack of drugs, equipment and trained personnel has a negative impact on goals such as reducing child and maternal mortality, HIV transmission, malaria and other diseases.
Apparently, drugs and equipment can be stolen or may never reach health facilities. Sometimes patients have to bring the latex gloves and other equipment that will be used for their care. Perhaps sometimes equipment in short supply is reused, even without proper sterilization. But accepting that it can happen is not enough. It also needs to be established if this is contributing to transmission of diseases, such as HIV, and if so, how big this contribution is.
It's all very well to talk/write about destigmatization. But many of those doing the talking/writing are also doing the stigmatizing. There is plenty of evidence that HIV is not always transmitted sexually in Africa and there is evidence that possible cases of non-sexual transmission need to be investigated. Admitting this would go a long way towards reducing transmission, and also reducing stigmatization.
You will no more reduce stigmatization by saying 'stigma is bad' than you will influence sexual behavior by saying 'unprotected sex is risky'. We have learned that through many years of failing to have much impact on HIV transmission. The issue of stigma is very much in the hands of the people who warn us about how damaging it is, the UN, UNAIDS, WHO, CDC, the World Bank, etc.
The best way to reduce HIV transmission is to be clear about how the virus is being transmitted and not to depend on out of date and inappropriate figures. The best way to reduce mother to child transmission is to reduce the number of mothers being infected. And the best way to reduce stigma is to be honest about HIV transmission: we know that it is not always transmitted sexually and we don't even know how much is transmitted sexually.
Monday, June 13, 2011
Are UNAIDS Getting Off On Their Own Sexual Fantasies?
If paying for sex commoditizes it, does paying people not to have sex also commoditize it? Would anyone bribe their daughter with money to wait till they are married before they have sex? Or would they bribe them with money not to have sex for money? Somehow, I can't imagine parents thinking this way.
I don't know if paying girls not to have sex commoditizes it but I know it's one of the stories that does the rounds because it seems to appeal to journalists. And I know that UNAIDS sees it as worth a try in South Africa. I just can't see them trying it out in Washington DC (which might have the highest HIV rates in the Western world).
The article informs us that young South African girls are "one of the highest risk groups, because poverty drives them to have sex in exchange for gifts." What, all young girls? Or is it just all 'poor' young girls? "Researchers now want to see whether using cash payments as a reward for getting good grades and having annual HIV tests could curb the girls' risky sexual behaviour." So if the grades are not good and/or they don't have annual tests for some reason, no money for them?
Maybe things have changed radically in SA but only a few years ago "Startling new evidence from a three-year survey [showed] that HIV is now growing fastest among those who are wealthier and educated." This phenomenon is quite familiar in Kenya and even more so in Tanzania. In fact, the phenomenon is most marked among female Tanzanians: HIV rates are higher among well educated, well off Tanzanian women.
The Nature article is not too clear but I think it is saying that money is being given to boys and girls. Apparently boys are being involved because "Men are driving the epidemic — through their sexual behaviours, drug-taking, risk-taking and the fact that they often hold the balance of power in decision-making in intimate relationships."
Maybe the epidemic is being driven by men, but people could be forgiven for not being entirely convinced of that. HIV prevalence among females at age 15-19 is 6.7% and among males it is only 2.5%. We are informed, frequently, that young women sleep with older men. But how much older? And do all young women sleep with older men? Because in the 20-24 age group, female prevalence is 21.1% and male only 5.1.
Some estimates suggest that some (but by no means all) females sleep with men who are between five and ten years older than them. So if 15-19 year old females were sleeping with 20-24 year old men, it looks like a lot of the males are actually being infected by females, not the other way around. 6.7% of 15-19 year old females are infected, compared to 5.1% of 20-24 year old males. Sorry for being repetitive but these figures don't suggest that HIV transmission is being 'driven by men'.
Even if some young women have sex with much older men, there is no evidence that they all do. And while female prevalence peaks at 32.7% in the 25-29 year age group, it peaks at only 25.8% among 30-34 year old males, never reaching female prevalence rates in any age group. The figures could even suggest that the number of promiscuous females, if you go for the promiscuity theory of HIV transmission, radically outnumbers that of promiscuous males.
This doesn't really give credence to the idea that the epidemic is being driven by men. In fact, it might make you question the assumption that the epidemic is entirely driven by sex. You have huge numbers of females being infected at a very young age and far smaller numbers of men who could be infecting them. The whole principle behind making money from sex is that there are relatively few women being paid by a relatively large number of men.
If the number of women selling sex outnumbers the men buying it, the bottom falls out of the market. But, interestingly, if fewer women are willing to sell sex, the value will go up. If lots of these young females, said to be selling sex because they are so impoverished, suddenly disappear off the market, those left selling sex will be able to command a far higher price. The scheme may have some benefit, but probably not the one intended by UNAIDS!
But the two main claims in the article about paying young women not to have sex are that HIV is driven by large numbers of poor young women having sex for money and that HIV transmission is driven by (smaller numbers of) promiscuous men. Neither of these claims seems very plausible. What is plausible is that small numbers of poor young women have sex for money and that small numbers of promiscuous men pay for sex.
And this still doesn't explain extraordinarily high HIV prevalence figures found in South Africa, therefore it can not justify paying young girls (or boys) to not have sex. HIV prevention interventions need to be based on reality, rather than on the fantasies of a bunch of bureaucrats desperate to have something to show for the billions that have been poured into their institution.
Enabling girls to stay in school has been shown to reduce 'unsafe' sex, unplanned pregnancies and possibly sexually transmitted infections and HIV. But if HIV prevalence is usually higher among better educated girls, perhaps this needs to be investigated before spending money and precious time with interventions that may not work and that may make things worse. There is no substitute for establishing exactly how HIV is being transmitted in high prevalence contexts. Because we clearly don't know that yet.
I don't know if paying girls not to have sex commoditizes it but I know it's one of the stories that does the rounds because it seems to appeal to journalists. And I know that UNAIDS sees it as worth a try in South Africa. I just can't see them trying it out in Washington DC (which might have the highest HIV rates in the Western world).
The article informs us that young South African girls are "one of the highest risk groups, because poverty drives them to have sex in exchange for gifts." What, all young girls? Or is it just all 'poor' young girls? "Researchers now want to see whether using cash payments as a reward for getting good grades and having annual HIV tests could curb the girls' risky sexual behaviour." So if the grades are not good and/or they don't have annual tests for some reason, no money for them?
Maybe things have changed radically in SA but only a few years ago "Startling new evidence from a three-year survey [showed] that HIV is now growing fastest among those who are wealthier and educated." This phenomenon is quite familiar in Kenya and even more so in Tanzania. In fact, the phenomenon is most marked among female Tanzanians: HIV rates are higher among well educated, well off Tanzanian women.
The Nature article is not too clear but I think it is saying that money is being given to boys and girls. Apparently boys are being involved because "Men are driving the epidemic — through their sexual behaviours, drug-taking, risk-taking and the fact that they often hold the balance of power in decision-making in intimate relationships."
Maybe the epidemic is being driven by men, but people could be forgiven for not being entirely convinced of that. HIV prevalence among females at age 15-19 is 6.7% and among males it is only 2.5%. We are informed, frequently, that young women sleep with older men. But how much older? And do all young women sleep with older men? Because in the 20-24 age group, female prevalence is 21.1% and male only 5.1.
Some estimates suggest that some (but by no means all) females sleep with men who are between five and ten years older than them. So if 15-19 year old females were sleeping with 20-24 year old men, it looks like a lot of the males are actually being infected by females, not the other way around. 6.7% of 15-19 year old females are infected, compared to 5.1% of 20-24 year old males. Sorry for being repetitive but these figures don't suggest that HIV transmission is being 'driven by men'.
Even if some young women have sex with much older men, there is no evidence that they all do. And while female prevalence peaks at 32.7% in the 25-29 year age group, it peaks at only 25.8% among 30-34 year old males, never reaching female prevalence rates in any age group. The figures could even suggest that the number of promiscuous females, if you go for the promiscuity theory of HIV transmission, radically outnumbers that of promiscuous males.
This doesn't really give credence to the idea that the epidemic is being driven by men. In fact, it might make you question the assumption that the epidemic is entirely driven by sex. You have huge numbers of females being infected at a very young age and far smaller numbers of men who could be infecting them. The whole principle behind making money from sex is that there are relatively few women being paid by a relatively large number of men.
If the number of women selling sex outnumbers the men buying it, the bottom falls out of the market. But, interestingly, if fewer women are willing to sell sex, the value will go up. If lots of these young females, said to be selling sex because they are so impoverished, suddenly disappear off the market, those left selling sex will be able to command a far higher price. The scheme may have some benefit, but probably not the one intended by UNAIDS!
But the two main claims in the article about paying young women not to have sex are that HIV is driven by large numbers of poor young women having sex for money and that HIV transmission is driven by (smaller numbers of) promiscuous men. Neither of these claims seems very plausible. What is plausible is that small numbers of poor young women have sex for money and that small numbers of promiscuous men pay for sex.
And this still doesn't explain extraordinarily high HIV prevalence figures found in South Africa, therefore it can not justify paying young girls (or boys) to not have sex. HIV prevention interventions need to be based on reality, rather than on the fantasies of a bunch of bureaucrats desperate to have something to show for the billions that have been poured into their institution.
Enabling girls to stay in school has been shown to reduce 'unsafe' sex, unplanned pregnancies and possibly sexually transmitted infections and HIV. But if HIV prevalence is usually higher among better educated girls, perhaps this needs to be investigated before spending money and precious time with interventions that may not work and that may make things worse. There is no substitute for establishing exactly how HIV is being transmitted in high prevalence contexts. Because we clearly don't know that yet.
Thursday, June 9, 2011
HIV Treatment Has Come a Long Way, Prevention Has a Long Way to Go
South Africa, apparently, has a plan to "eliminate HIV in the next 30 years". The plan is based on a mathematical model, which assumes very high HIV prevalence and a population that will be tested once a year. Those found positive will be given antiretroviral drugs immediately, to take for the rest of their lives. The model says that this will eliminate the epidemic.
It would be interesting to know what figures they used in their model. South Africa has indeed tested many millions of people in the last twelve months, perhaps 12 million or more. But it has been estimated that people might need to be tested more frequently than once a year, perhaps twice or even four times a year. Will once a year be feasible, even if it turns out to be enough?
Sure, plenty of research has shown that a lot of people responding to antiretroviral treatment have a very low viral load and are unlikely to transmit the virus to their sexual partners. But that doesn't mean that 'test and treat', as it's called, will eradicate transmission altogether.
Recent research which gave rise to a lot of the hype about test and treat involved discordant couples. These are couples where only one person, the 'index case', is infected. It is believed that the index case will, sooner or later, infect their partner if they continue to have unprotected sex. The rate of transmission in discordant relationships is, indeed, very high. Putting the infected partners on drugs, assuming that they are found to be HIV positive early enough, could significantly reduce the risk to the HIV negative partner.
But that doesn't answer the question of how the index partner was infected. They would probably not have been protected by a test and treat policy, unless that policy was able to ensure that a huge percentage of new infections were discovered and treated very early on. But, while you can see the motivation for putting the HIV positive partner on drugs to protect the negative partner in discordant couples, in a couple where neither is positive there is no such motivation.
The South African plan doesn't deal with the issue of whether all HIV positive people will agree to or adhere to treatment. It doesn't even ask if putting people on treatment immediately is the best thing for those people's health. Leaving treatment till too late is clearly bad for people's health. But treating them too early, as well as being expensive and more likely to result in non-adherence and consequent resistance, may not be ethical.
It certainly won't be ethical if people are compelled to take the drugs, regardless of whether they need them or not. But there's also the question of whether people should take drugs for the benefit of others, or for the benefit of public health. [There's an interesting discussion of patient autonomy by Dr Joseph Sonnabend on his POZ blog.]
Treating more people, if and when they need treatment, is a good thing. Testing more people and testing them regularly is also good, especially if the results of such widespread testing are used to figure out why so many people become infected in South Africa. But test and treat alone is very unlikely to eliminate any epidemic in any country in 30 years, or even in 100 years.
No matter what any model (or 'expert') tells you, treating as many HIV positive people as possible is not the same as developing strategies to ensure that people don't become infected in the first place. Public health is a lot more complicated than any mathetical model can show. That's why so few diseases have ever been eradicated.
Diseases that have been virtually eradicated in some countries were not eradicated merely because of some powerful technology, either. They were eradicated because the conditions under which the disease is transmitted were also addressed. Water, sanitation and hygiene in the case of many diseases, air quality and habitation in the case of others, food and nutrition, living conditions, working conditions, etc. Test and treat remains relatively blind to the conditions under which HIV is transmitted (as has the HIV industry).
Alarmingly, research has shown that test and treat alone will not even come close to eradicating HIV in the US, where transmission is many times lower than in South Africa and the amount per head spent on healthcare is the highest in the world. And this is not because the universal testing part of the strategy is not in operation but because only 1 in 5 people on treatment have the undetectable viral load requried to ensure that they don't infect their partner through unprotected sex.
Test and treat is neither a miracle nor something that is impossible to effect. But it will not eradicate HIV epidemics, ever, anywhere. And public health experts should know that there is no such precedent for eradicating a disease that is transmitted in a number of ways (some of which are adequately acknowledged and some of which are not). It is wholly irresponsible to make the implicit promises that one hears constantly about test and treat.
There is a lot we don't yet know about HIV transmission and, apparently, a lot we are not very anxious to discuss. So let's not get distracted from HIV prevention by what is just one in a long line of hyped technical fixes. Test and treat, treatment as prevention, whatever you want to call it, will only ever be part of an effective strategy to eradicate HIV.
Wednesday, June 8, 2011
One Unsupported Assumption Can Infect a Whole Body of Research
The author of a book on AIDS with one of the most stigmatizing titles possible, Elizabeth Pisani, is interviewed by IRIN about why HIV prevention efforts have failed to curb the spread of the pandemic. One of the answers she gives is that we started too late, which I guess suggests that she thinks we have started now.
She's right about missing an important opportunity by not implementing needle exchange programs in some countries where the bulk of HIV transmission continues to occur among injecting drug users. Russia and a lot of Central and Eastern Europe are still dithering about such programs and the US continues to deprecate them, though they have worked well in countries where they have been implemented.
She's a bit wide of the mark in claiming that not targeting sex workers to reduce sexually transmitted infections represents a missed opportunity, certainly in the case of developing countries, anyhow. Trials on the impact of such interventions showed that they had little effect in reducing HIV transmission and some of them may have even increased the risks of non-sexual transmission for participants.
Pisani is right about abstinence not working very well but she failed to influence attitudes towards that 'strategy' when she was working at UNAIDS. But now that she's a rebel, working at the London School of Hygiene and Tropical Medicine, that bastion of public health reaction, going along with the HIV industry line that almost all HIV transmission in African countries results from heterosexual sex is unlikely to change things much.
Again, Pisani is right that the 'all men are evil, all women are innocent' reflex is not helpful and never has been. But she fails to mention the extent to which women are affected by HIV in comparison to men. Overall in Africa, in excess of 60% of HIV positive people are women and among young people, the figure is in excess of 70%. HIV prevention activity has failed to address that and the industry seems oblivious to it.
Pisani still holds her stigmatizing view of HIV transmission as being a matter of promiscuity, which it is not, and never has been. Data about sexual behavior, such as it is, shows that those who are infected with HIV often faced lower sexual risk than many who were not infected and some who took precautions were even more likely to be infected than some who did not. The idea that HIV is mainly about sex is unsupported by evidence, but still the mainstream view.
Treatment as prevention, we are told, is not the answer to ending HIV transmission. But anyone who thinks the strategy will address the needs of any more than a small subset of people has been brainwashed, anyway. But this is not an argument against expanding the number of people receiving treatment. So far, so good.
The author of the Wisdom of Whores, surprisingly, admits that she doesn't know what is the best approach to HIV prevention in sub-Saharan Africa. And she seems to have some intuition that incidence, the yearly rate of new infections, might rise. Unfortunately, we are not told what is behind this intuition so it's hard to say if it's one of her good ones or one of her not so good ones.
Ultimately, Pisani doesn't touch on the great elephant in the UNAIDS room: why a virus that is difficult to transmit heterosexually is said to be almost always transmitted heterosexually, but only in Africa, where sexual behavior is little different from that in many other places. She has never justified the highly stigmatizing title of her book, nor the attitude towards Africans which has had, and continues to have, so much influence on HIV policy.
Indeed, Pisani is one of the people behind the kind of dubious research and mathematical modelling that so much current HIV thinking is based on. The claim that HIV is mainly transmitted sexually in African countries, and hardly ever transmitted through non-sexual modes, is supported by the flimisiest evidence, at best. Until this massive flaw in mainstream HIV thinking is revised, prevention efforts will continue to have little impact on epidemics.
She's right about missing an important opportunity by not implementing needle exchange programs in some countries where the bulk of HIV transmission continues to occur among injecting drug users. Russia and a lot of Central and Eastern Europe are still dithering about such programs and the US continues to deprecate them, though they have worked well in countries where they have been implemented.
She's a bit wide of the mark in claiming that not targeting sex workers to reduce sexually transmitted infections represents a missed opportunity, certainly in the case of developing countries, anyhow. Trials on the impact of such interventions showed that they had little effect in reducing HIV transmission and some of them may have even increased the risks of non-sexual transmission for participants.
Pisani is right about abstinence not working very well but she failed to influence attitudes towards that 'strategy' when she was working at UNAIDS. But now that she's a rebel, working at the London School of Hygiene and Tropical Medicine, that bastion of public health reaction, going along with the HIV industry line that almost all HIV transmission in African countries results from heterosexual sex is unlikely to change things much.
Again, Pisani is right that the 'all men are evil, all women are innocent' reflex is not helpful and never has been. But she fails to mention the extent to which women are affected by HIV in comparison to men. Overall in Africa, in excess of 60% of HIV positive people are women and among young people, the figure is in excess of 70%. HIV prevention activity has failed to address that and the industry seems oblivious to it.
Pisani still holds her stigmatizing view of HIV transmission as being a matter of promiscuity, which it is not, and never has been. Data about sexual behavior, such as it is, shows that those who are infected with HIV often faced lower sexual risk than many who were not infected and some who took precautions were even more likely to be infected than some who did not. The idea that HIV is mainly about sex is unsupported by evidence, but still the mainstream view.
Treatment as prevention, we are told, is not the answer to ending HIV transmission. But anyone who thinks the strategy will address the needs of any more than a small subset of people has been brainwashed, anyway. But this is not an argument against expanding the number of people receiving treatment. So far, so good.
The author of the Wisdom of Whores, surprisingly, admits that she doesn't know what is the best approach to HIV prevention in sub-Saharan Africa. And she seems to have some intuition that incidence, the yearly rate of new infections, might rise. Unfortunately, we are not told what is behind this intuition so it's hard to say if it's one of her good ones or one of her not so good ones.
Ultimately, Pisani doesn't touch on the great elephant in the UNAIDS room: why a virus that is difficult to transmit heterosexually is said to be almost always transmitted heterosexually, but only in Africa, where sexual behavior is little different from that in many other places. She has never justified the highly stigmatizing title of her book, nor the attitude towards Africans which has had, and continues to have, so much influence on HIV policy.
Indeed, Pisani is one of the people behind the kind of dubious research and mathematical modelling that so much current HIV thinking is based on. The claim that HIV is mainly transmitted sexually in African countries, and hardly ever transmitted through non-sexual modes, is supported by the flimisiest evidence, at best. Until this massive flaw in mainstream HIV thinking is revised, prevention efforts will continue to have little impact on epidemics.
Sunday, June 5, 2011
The Myth about HIV and Sex: 30 Years in the Making
Today marks the 30th anniversary of the discovery of HIV. When the virus was discovered, it was still being transmitted rapidly in high prevalence countries, mostly in Africa. But over the ten years or so following its discovery, transmission declined, even in high prevalence countries. In Kenya, incidence peaked in the early to mid 1990s, almost a decade before the government even admitted that there was a HIV epidemic there.
Similar patterns are found in other countries. HIV incidence peaked before most people had even heard of the virus, many years before in most countries in Africa. So why did the virus decline? Because people who had spontaneously begun to have outrageous amounts of sex in the late 1970s and early 1980s, just as spontaneously ceased to have such outrageous amounts of sex in the late 1980s and early 1990s, and that trend continued up to the present?
That's what the HIV industry would have you believe, anyhow. For them, something like that story is true, although they don't ask why people would suddenly and profoundly change their sexual habits twice in the space of less than 20 years. And they don't allude to the fact that incidence, the yearly rate of new infections, peaked and declined long before mass HIV 'prevention' campaigns even started.
Thirty years ago, it was still permissble to talk about there being several ways for HIV to be transmitted, especially in a rich country context. After all, it was hardly ever transmitted through heterosexual sex in rich countries and it is even less so now. In rich countries, HIV was always transmitted mainly through men having sex with men and intravenous drug use. But talk of non-sexual transmission has declined significantly over the last 30 years.
In African countries, HIV was first noticed to reach massive levels in sex worker populations. In Kenya, prevalence is said to have reached over 80%, in Tanzania, over 70%. And this is in populations where hardly any men were infected. The fact that these ridiculous and completely unacceptable levels were found in sex workers who had been put through sexually transmitted infection (STI) programs has since been conveniently ignored. As I said, talk about such things has declined.
Fingers have been pointed, but in rich countries those fingers were pointed at men who have sex with men and intravenous drug users. Sex workers were also implicated but it's hard to see why because HIV rates were always low, except among sex workers who were also intravenous drug users.
But in African countries, fingers were pointed at men who have sex with men, commercial sex workers, truckers, soldiers, police, prisoners, internal migrants, migrant workers, internally displaced persons, fishing populations, those who engage in 'cultural practices' (such as wife inheritance, ritual cleansing, etc), teachers, 'sugar daddies', clients of commercial sex workers, partners of men who have sex with men, uncircumcised men, circumcised women, polygamists, bigamists, alcohol users, khat chewers, (non-injecting) drug users, sex tourists, Ugandans, young women and girls, older men who marry younger women, and the list goes on.
Most of these groups are still considered to be 'most at risk' populations or 'MARP'. And yet, modes of transmission surveys show that in African countries, the biggest groups of HIV positive people engage in low risk sex. Those surveys completely ignore the fact that many HIV positive people don't engage in sex at all, or hardly at all, those who take precautions are often more likely to be infected than those who do not and various other details which don't fit into the picture of the sexually animalistic African that UNAIDS has built up over the years.
UNAIDS often bandies about authoritative sounding figures, such as that 80% (sometimes even 90%) of HIV in some African countries is heterosexually transmitted. But it's interesting to see what these modes of transmission surveys are based on. There is an oft cited article that seems to have a disproportionate influence on HIV policy documents by Eleanor Gouws and others but this is based on a simplistic piece of mathematical modelling with some highly questionable figures.
If you don't believe that the mathematical model is simplistic and that the figures are questionable, you can download it and play around with it. You might be struck by the transmission probability per risky exposure act, for example. The risk for sex workers is dubious, but the risk for clients, at half the risk for sex workers, is even more so. And the risk for clients' partners is the same as that for sex workers, as is that of various other groups.
The risk for casual heterosexual sex, partners of those who engage in casual heterosexual sex and low-risk heterosexual sex is questionable enough as well. And only 10% of the population are deemed to have no risk from their sexual behavior. That's in African populations, of course! As I've said, heterosexual sex poses little or no risk to people outside of a few African countries, even in certain parts of some high prevalence African countries (such as Zanzibar and Kenya's North Eastern Province, where prevalence is lower than in a lot of US cities).
But the most laughable parts of the model relate to risks from unsafe medical injections and blood transfusions. Gouws estimated these risks to be very low, contributing less than 1% of all infections. UNAIDS ups that figure to a little over 2% when you add unsafe injections and unsafe blood transfusions together. However, this ignores any other kind of medical risk, such as from contaminated gloves, instruments and machinery of various kinds in sub-standard hospitals, wielded by poorly trained, underequipped personnel. (You can try plugging in some of the figures from here, or just make some up. UNAIDS did.)
Anyhow, the transmission probability per risky exposure act for these two items is absurd. You can try the model with a more reasonable value, even if it's just the figure for injecting drug use, and you get a far more credible estimate for the contribution of unsafe healthcare including, but not limited to, unsterile injections. And if you change the number of injections per year to something more reasonable you will also see the contribution of these non-sexual transmission modes rocketing up.
Looking at figures provided by the Kenyan Demographic and Health Survey (or the Tanzanian one, or that for many other African countries) you would be forgiven for thinking that females tend to become infected first and later infect their male partners. Far more females are infected than males, they are infected at earlier ages and rates exceed rates for males until many years of sexual activity have passed. In some population groups the number of females infected can exceed the number of males infected by 4 or 5 to one.
Does this mean that HIV is not almost always heterosexually transmitted? Certainly not. Nor does it mean that non-sexual transmission, such as through unsafe healthcare, is high, let alone higher than heterosexual transmission. It means that we don't have the faintest idea how high non-sexual HIV transmission is, relative to heterosexual transmission. And if you are puzzled at the fact that HIV prevalence is highest among young heterosexual women in a few African countries, and virtually nowhere else in the world, then you are awake (and almost certainly not working for UNAIDS or any of the HIV industry).
And yet, not only are men who have sex with men and intravenous drug users hardly ever targeted in high prevalence countries, but sex workers are not even targeted consistently in most. 'Prevention' spending represents less than 25% of HIV spending in countries like Kenya. How much less is unclear because about 80% of that is spent on unspecified prevention activities. In other words, no one has a clue what it's being spent on and they probably don't care Even youth are not a particularly lucky group, receiving only about 5% of prevention spending. And that shows. Over 70% of infected youth in African countries are females.
And who infects them? Well, if 80% (or 90%) of transmission is heterosexual, men, of course. But which men? UNAIDS and the HIV industry can't say. Give them another thirty years of highly distorting funding and they may modify their answer. Some patterns may be consistent with HIV being sexually transmitted, but this does not mean that it always is. And some patterns are consistent with HIV being transmitted in STI clinics and other medical facilities.
But read around the data on non-sexual HIV transmission, especially unsterile injections, and you'll find that there is "Very little information on injections safety" and that it is "hard to get baselines". In fact, there is "no data about the quality of service provision". This is also a good time to look at the latest Service Provision Assessment for Kenya, which won't tell you as much about quality as it does about quantity.
The Modes of Transmission conclusion about service provision is brief, but telling: "in the future, Kenya will have to spend more time and effort analysing and assessing the quality of services provided – providing a bad service (particularly in the sensitive areas of sexual behaviour) may be worse than not providing a service at all."
What could this mean? Could it mean that the many people who do not have access to any health facilities might thereby be avoiding infection with HIV, hepatitis and various other diseases? Could it mean that people who get large numbers of injections in STI clinics every year, for STIs, hormonal contraception, etc, might face a high risk of HIV and other infection there?
HIV prevalence figures in both Kenya and Tanzania tend to be lower in areas where people have little or no access to healthcare. Unprotected sex tends to be more common in those areas. It doesn't take a genius to work out that HIV is not all about sex, but also that it could have an awful lot to do with unsafe healthcare. If even UNAIDS could inadvertently come to that conclusion, anyone can. But now it's time for UNAIDS to do what they have avoided doing for so many years: empirical research into the relative contribution of non-sexual HIV transmission in high HIV prevalence countries.
Similar patterns are found in other countries. HIV incidence peaked before most people had even heard of the virus, many years before in most countries in Africa. So why did the virus decline? Because people who had spontaneously begun to have outrageous amounts of sex in the late 1970s and early 1980s, just as spontaneously ceased to have such outrageous amounts of sex in the late 1980s and early 1990s, and that trend continued up to the present?
That's what the HIV industry would have you believe, anyhow. For them, something like that story is true, although they don't ask why people would suddenly and profoundly change their sexual habits twice in the space of less than 20 years. And they don't allude to the fact that incidence, the yearly rate of new infections, peaked and declined long before mass HIV 'prevention' campaigns even started.
Thirty years ago, it was still permissble to talk about there being several ways for HIV to be transmitted, especially in a rich country context. After all, it was hardly ever transmitted through heterosexual sex in rich countries and it is even less so now. In rich countries, HIV was always transmitted mainly through men having sex with men and intravenous drug use. But talk of non-sexual transmission has declined significantly over the last 30 years.
In African countries, HIV was first noticed to reach massive levels in sex worker populations. In Kenya, prevalence is said to have reached over 80%, in Tanzania, over 70%. And this is in populations where hardly any men were infected. The fact that these ridiculous and completely unacceptable levels were found in sex workers who had been put through sexually transmitted infection (STI) programs has since been conveniently ignored. As I said, talk about such things has declined.
Fingers have been pointed, but in rich countries those fingers were pointed at men who have sex with men and intravenous drug users. Sex workers were also implicated but it's hard to see why because HIV rates were always low, except among sex workers who were also intravenous drug users.
But in African countries, fingers were pointed at men who have sex with men, commercial sex workers, truckers, soldiers, police, prisoners, internal migrants, migrant workers, internally displaced persons, fishing populations, those who engage in 'cultural practices' (such as wife inheritance, ritual cleansing, etc), teachers, 'sugar daddies', clients of commercial sex workers, partners of men who have sex with men, uncircumcised men, circumcised women, polygamists, bigamists, alcohol users, khat chewers, (non-injecting) drug users, sex tourists, Ugandans, young women and girls, older men who marry younger women, and the list goes on.
Most of these groups are still considered to be 'most at risk' populations or 'MARP'. And yet, modes of transmission surveys show that in African countries, the biggest groups of HIV positive people engage in low risk sex. Those surveys completely ignore the fact that many HIV positive people don't engage in sex at all, or hardly at all, those who take precautions are often more likely to be infected than those who do not and various other details which don't fit into the picture of the sexually animalistic African that UNAIDS has built up over the years.
UNAIDS often bandies about authoritative sounding figures, such as that 80% (sometimes even 90%) of HIV in some African countries is heterosexually transmitted. But it's interesting to see what these modes of transmission surveys are based on. There is an oft cited article that seems to have a disproportionate influence on HIV policy documents by Eleanor Gouws and others but this is based on a simplistic piece of mathematical modelling with some highly questionable figures.
If you don't believe that the mathematical model is simplistic and that the figures are questionable, you can download it and play around with it. You might be struck by the transmission probability per risky exposure act, for example. The risk for sex workers is dubious, but the risk for clients, at half the risk for sex workers, is even more so. And the risk for clients' partners is the same as that for sex workers, as is that of various other groups.
The risk for casual heterosexual sex, partners of those who engage in casual heterosexual sex and low-risk heterosexual sex is questionable enough as well. And only 10% of the population are deemed to have no risk from their sexual behavior. That's in African populations, of course! As I've said, heterosexual sex poses little or no risk to people outside of a few African countries, even in certain parts of some high prevalence African countries (such as Zanzibar and Kenya's North Eastern Province, where prevalence is lower than in a lot of US cities).
But the most laughable parts of the model relate to risks from unsafe medical injections and blood transfusions. Gouws estimated these risks to be very low, contributing less than 1% of all infections. UNAIDS ups that figure to a little over 2% when you add unsafe injections and unsafe blood transfusions together. However, this ignores any other kind of medical risk, such as from contaminated gloves, instruments and machinery of various kinds in sub-standard hospitals, wielded by poorly trained, underequipped personnel. (You can try plugging in some of the figures from here, or just make some up. UNAIDS did.)
Anyhow, the transmission probability per risky exposure act for these two items is absurd. You can try the model with a more reasonable value, even if it's just the figure for injecting drug use, and you get a far more credible estimate for the contribution of unsafe healthcare including, but not limited to, unsterile injections. And if you change the number of injections per year to something more reasonable you will also see the contribution of these non-sexual transmission modes rocketing up.
Looking at figures provided by the Kenyan Demographic and Health Survey (or the Tanzanian one, or that for many other African countries) you would be forgiven for thinking that females tend to become infected first and later infect their male partners. Far more females are infected than males, they are infected at earlier ages and rates exceed rates for males until many years of sexual activity have passed. In some population groups the number of females infected can exceed the number of males infected by 4 or 5 to one.
Does this mean that HIV is not almost always heterosexually transmitted? Certainly not. Nor does it mean that non-sexual transmission, such as through unsafe healthcare, is high, let alone higher than heterosexual transmission. It means that we don't have the faintest idea how high non-sexual HIV transmission is, relative to heterosexual transmission. And if you are puzzled at the fact that HIV prevalence is highest among young heterosexual women in a few African countries, and virtually nowhere else in the world, then you are awake (and almost certainly not working for UNAIDS or any of the HIV industry).
And yet, not only are men who have sex with men and intravenous drug users hardly ever targeted in high prevalence countries, but sex workers are not even targeted consistently in most. 'Prevention' spending represents less than 25% of HIV spending in countries like Kenya. How much less is unclear because about 80% of that is spent on unspecified prevention activities. In other words, no one has a clue what it's being spent on and they probably don't care Even youth are not a particularly lucky group, receiving only about 5% of prevention spending. And that shows. Over 70% of infected youth in African countries are females.
And who infects them? Well, if 80% (or 90%) of transmission is heterosexual, men, of course. But which men? UNAIDS and the HIV industry can't say. Give them another thirty years of highly distorting funding and they may modify their answer. Some patterns may be consistent with HIV being sexually transmitted, but this does not mean that it always is. And some patterns are consistent with HIV being transmitted in STI clinics and other medical facilities.
But read around the data on non-sexual HIV transmission, especially unsterile injections, and you'll find that there is "Very little information on injections safety" and that it is "hard to get baselines". In fact, there is "no data about the quality of service provision". This is also a good time to look at the latest Service Provision Assessment for Kenya, which won't tell you as much about quality as it does about quantity.
The Modes of Transmission conclusion about service provision is brief, but telling: "in the future, Kenya will have to spend more time and effort analysing and assessing the quality of services provided – providing a bad service (particularly in the sensitive areas of sexual behaviour) may be worse than not providing a service at all."
What could this mean? Could it mean that the many people who do not have access to any health facilities might thereby be avoiding infection with HIV, hepatitis and various other diseases? Could it mean that people who get large numbers of injections in STI clinics every year, for STIs, hormonal contraception, etc, might face a high risk of HIV and other infection there?
HIV prevalence figures in both Kenya and Tanzania tend to be lower in areas where people have little or no access to healthcare. Unprotected sex tends to be more common in those areas. It doesn't take a genius to work out that HIV is not all about sex, but also that it could have an awful lot to do with unsafe healthcare. If even UNAIDS could inadvertently come to that conclusion, anyone can. But now it's time for UNAIDS to do what they have avoided doing for so many years: empirical research into the relative contribution of non-sexual HIV transmission in high HIV prevalence countries.
Sunday, February 27, 2011
Paid to Fail: the Politics of HIV Research
I recently commented on a much hyped but relatively vacuous paper by Halperin, Mugurungi, Hallett, Muchini, Campbell, Magure, Benedikt and Gregson, entitled 'A Surprising Prevention Success: Why Did the HIV Epidemic Decline in Zimbabwe?'
But there was one item in the paper I didn't comment on that has stuck in my mind since. They write: "Many men in focus groups and interviews reported that having less disposable income has increasingly led to reduced ability to purchase sex or maintain multiple sexual relationships".
The sentence sounds reasonable enough if you accept the overall conclusion of the paper, that changes in sexual behavior driven by fear of HIV infection resulted in massive reductions in HIV transmission. But the data used by the paper only shows minor changes in sexual behavior. In truth, correlations between sexual behavior and HIV transmission are as unconvincing as they always have been, in Zimbabwe and elsewhere.
But even thinking about this sentence from an economic point of view and the little we know about commercial sex, does having less disposable income necessarily result in a reduced likelihood of purchasing sex? I think the real worry when money becomes scarce is that those who depend on providing sexual services for money have to settle for less money or provide more and/or riskier services.
Of course, such hypotheses need to be tested and many HIV researchers are reluctant to carry out rigorous research into sexual behavior. If sex turned out to be less relevant to HIV it's likely that funding would dry up. And if HIV prevention turned out to be a matter of providing decent health care, those currently selling drugs would also quickly lose interest.
There must be a lot of money in providing safe health care but it doesn't seem to attract the donors. But then, it's important to sell HIV drugs to developing countries because that's where the bulk of the market is. The same can't be said for other health care goods and services; not yet, anyhow.
Another problem with the idea that commercial sex becomes less common when money is scarce is that you'd think the trend for wealthier people to be infected in greater numbers than poorer people would reverse. This trend has reversed in some countries, but not noticeably as a result of economic changes.
The authors of the paper in question put a lot of credence in focus group discussions and that seems unwise. But it's their analysis of those findings that seem most disingenuous. The analysis appears to be independent of the data on sexual behavior, probably because the data is the same in high prevalence countries as it is in low prevalence countries. It's almost as if they are saying "here's the data, it contradicts our conclusions but everyone knows our conclusions are true anyway".
Because this paper doesn't even give a convincing pretense of having any substance, I'm still wondering what is behind it. The authors are very well established so the only reason I can think of that they would put their names to such rubbish is that they know no one really cares how they come to their conclusion as long as they come to the approved conclusion. But it seems like an expensive and circuitous way of failing to reduce HIV transmission.
But there was one item in the paper I didn't comment on that has stuck in my mind since. They write: "Many men in focus groups and interviews reported that having less disposable income has increasingly led to reduced ability to purchase sex or maintain multiple sexual relationships".
The sentence sounds reasonable enough if you accept the overall conclusion of the paper, that changes in sexual behavior driven by fear of HIV infection resulted in massive reductions in HIV transmission. But the data used by the paper only shows minor changes in sexual behavior. In truth, correlations between sexual behavior and HIV transmission are as unconvincing as they always have been, in Zimbabwe and elsewhere.
But even thinking about this sentence from an economic point of view and the little we know about commercial sex, does having less disposable income necessarily result in a reduced likelihood of purchasing sex? I think the real worry when money becomes scarce is that those who depend on providing sexual services for money have to settle for less money or provide more and/or riskier services.
Of course, such hypotheses need to be tested and many HIV researchers are reluctant to carry out rigorous research into sexual behavior. If sex turned out to be less relevant to HIV it's likely that funding would dry up. And if HIV prevention turned out to be a matter of providing decent health care, those currently selling drugs would also quickly lose interest.
There must be a lot of money in providing safe health care but it doesn't seem to attract the donors. But then, it's important to sell HIV drugs to developing countries because that's where the bulk of the market is. The same can't be said for other health care goods and services; not yet, anyhow.
Another problem with the idea that commercial sex becomes less common when money is scarce is that you'd think the trend for wealthier people to be infected in greater numbers than poorer people would reverse. This trend has reversed in some countries, but not noticeably as a result of economic changes.
The authors of the paper in question put a lot of credence in focus group discussions and that seems unwise. But it's their analysis of those findings that seem most disingenuous. The analysis appears to be independent of the data on sexual behavior, probably because the data is the same in high prevalence countries as it is in low prevalence countries. It's almost as if they are saying "here's the data, it contradicts our conclusions but everyone knows our conclusions are true anyway".
Because this paper doesn't even give a convincing pretense of having any substance, I'm still wondering what is behind it. The authors are very well established so the only reason I can think of that they would put their names to such rubbish is that they know no one really cares how they come to their conclusion as long as they come to the approved conclusion. But it seems like an expensive and circuitous way of failing to reduce HIV transmission.
Wednesday, February 9, 2011
Researchers Have No Opinion On Nosocomial HIV Infections in Zimbabwe
Non-sexual HIV transmission, when it's even discussed by the HIV orthodoxy, is usually dismissed with little argument and no evidence. What is most extraordinary is that one could hypothesize that both sexual and non-sexual transmission contribute to most epidemics and then try to work out the relative contribution of each. But they don't tend to do that.
Halperin, Mugurungi, Hallett, Muchini, Campbell, Magure, Benedikt and Gregson toe the party line in their recent paper 'A Surprising Prevention Success: Why Did the HIV Epidemic Decline in Zimbabwe?' They barely even mention non-sexual transmission and completely dismiss its significance.
But they do come to a very media friendly and quotable 'conclusion', that "fear of contracting the virus [is] the primary motivation for changes in sexual behavior". Journalists have pounced on this 'finding' and will continue spreading it for some time. Perhaps these researchers have recognized the value of media friendliness and found it to be more congenial than credible, enlightening research that could turn around the HIV pandemic.
Despite constant boasts about the number of people on antiretroviral treatment and the idea that you can contain an epidemic by throwing lots of drugs at it (which happens to be the current global treatment policy), these researchers even mention the very real possibility of drug resistance making mass treatment campaigns less sustainable than they currently are. They are in good company; Bill Gates recently said more less the same thing.
But what was their quotable conclusion based on? Well, they did a bit of mathematical modelling and read a few papers written by like-minded people (actually, the bibliography overlaps considerably with the list of authors), but they also give a lot of credence to a bunch of 'stakeholders', who certainly seemed to do a fair amount of agreeing with each other. Perhaps they see this as quantitative, their credence, the stakeholders' agreement, etc.
It's odd, when people say they have never had sex, never had unprotected sex or never had sex with anyone other than their partner (who is often HVI negative), they are unlikely to be believed, especially if they are African. But if they are like-minded people holed up in a hotel, their responses are treated at face value.
"[T]he unanimous conclusion from the stakeholders meeting held to assess, triangulate, and interpret the evidence assembled in the review was that a reduction in multiple sexual partnerships was the most likely proximate cause for the recent decline in HIV risk." What a surprise.
It goes on: "In assessing the underlying factors for the national prevalence decline, high AIDS mortality appears to have been the dominant factor for stimulating behavior change." Yet, high AIDS mortality has been a phenomenon in many countries that have had very high HIV prevalence. When lots of people become infected, lots of them die, widespread treatment regimes notwithstanding.
Similar claims used to be made about Uganda, though these researchers are also keeping Uganda at arm's length. Well, it's almost certainly true that some people were devastated by what they saw around them when huge numbers of people were dying terrible deaths. That would have some impact on anyone.
But the idea that it would be almost entirely responsible for levels of behavior change that resulted in a massive drop in rates of new infections in a short space of time in Zimbabwe, but nowhere else, is not credible. Nor is it even necessary to make such a foolish claim.
The economic decline experienced in Zimbabwe in the late 90s and early 2000s, we are told, played a considerable secondary role in amplifying patterns of behavior change. No doubt it did. But economic decline could also have resulted in fewer visits to the country's deteriorating health facilities, which would have reduced the number of nosocomial infections (infections resulting from medical treatment).
And what levels of behavior change occurred? From the figures cited, age of sexual debut and condom use barely changed. And multiple partnership indicators improved a bit, but these were never common enough to explain the almost umprecedented rates of transmission once found in the country. Most of these indicators wouldn't even look out of place in rich countries.
Interestingly, the researchers mention "the Zimbabwean government's early adoption of a home-based care policy [which] may inadvertently have accelerated the process of behavior change. It has been hypothesized that, when people die at home, this direct confrontation with AIDS mortality is more likely to result in a tangible fear of death among family and friends than when patients are primarily cared for in clinical facilities, such as in Botswana"
I'd interpret the effect of this policy rather differently. It could also have taken a lot of HIV positive people out of a health system that was not able to provide people with safe healthcare.
The authors conclude that significant changes in behavior are unlikely to have resulted from increasing levels of mortality alone. They also suggest that prevention programs provided people with information about the link between risky sexual behavior and HIV transmission. And they are probably right, to an extent. But why were these programs so successful in Zimbabwe when they failed so miserably elsewhere? The authors bluster on, unconvincingly.
Indeed, they don't even seem that convinced themselves. They can't really put their finger on anything much so they talk about "cumulative exposure" to prevention messages, as if that wouldn't have happened elsewhere. Similar claims have long been made to "explain" what happened in Uganda. After all, there must be some explanation, and if it has to be about sex this one is as good as any other.
I can understand a whole group of stakeholders churning out answers that would satisfy even a UNAIDS employee about the drivers of HIV. I have met few people who wouldn't say similar things. But I don't believe the authors could look on this this paper as a publishable piece of research. If they are all happy with it, then I am disgusted. Their own research screams for investigation of non-sexual transmission levels, but they carry on regardless.
Halperin, Mugurungi, Hallett, Muchini, Campbell, Magure, Benedikt and Gregson toe the party line in their recent paper 'A Surprising Prevention Success: Why Did the HIV Epidemic Decline in Zimbabwe?' They barely even mention non-sexual transmission and completely dismiss its significance.
But they do come to a very media friendly and quotable 'conclusion', that "fear of contracting the virus [is] the primary motivation for changes in sexual behavior". Journalists have pounced on this 'finding' and will continue spreading it for some time. Perhaps these researchers have recognized the value of media friendliness and found it to be more congenial than credible, enlightening research that could turn around the HIV pandemic.
Despite constant boasts about the number of people on antiretroviral treatment and the idea that you can contain an epidemic by throwing lots of drugs at it (which happens to be the current global treatment policy), these researchers even mention the very real possibility of drug resistance making mass treatment campaigns less sustainable than they currently are. They are in good company; Bill Gates recently said more less the same thing.
But what was their quotable conclusion based on? Well, they did a bit of mathematical modelling and read a few papers written by like-minded people (actually, the bibliography overlaps considerably with the list of authors), but they also give a lot of credence to a bunch of 'stakeholders', who certainly seemed to do a fair amount of agreeing with each other. Perhaps they see this as quantitative, their credence, the stakeholders' agreement, etc.
It's odd, when people say they have never had sex, never had unprotected sex or never had sex with anyone other than their partner (who is often HVI negative), they are unlikely to be believed, especially if they are African. But if they are like-minded people holed up in a hotel, their responses are treated at face value.
"[T]he unanimous conclusion from the stakeholders meeting held to assess, triangulate, and interpret the evidence assembled in the review was that a reduction in multiple sexual partnerships was the most likely proximate cause for the recent decline in HIV risk." What a surprise.
It goes on: "In assessing the underlying factors for the national prevalence decline, high AIDS mortality appears to have been the dominant factor for stimulating behavior change." Yet, high AIDS mortality has been a phenomenon in many countries that have had very high HIV prevalence. When lots of people become infected, lots of them die, widespread treatment regimes notwithstanding.
Similar claims used to be made about Uganda, though these researchers are also keeping Uganda at arm's length. Well, it's almost certainly true that some people were devastated by what they saw around them when huge numbers of people were dying terrible deaths. That would have some impact on anyone.
But the idea that it would be almost entirely responsible for levels of behavior change that resulted in a massive drop in rates of new infections in a short space of time in Zimbabwe, but nowhere else, is not credible. Nor is it even necessary to make such a foolish claim.
The economic decline experienced in Zimbabwe in the late 90s and early 2000s, we are told, played a considerable secondary role in amplifying patterns of behavior change. No doubt it did. But economic decline could also have resulted in fewer visits to the country's deteriorating health facilities, which would have reduced the number of nosocomial infections (infections resulting from medical treatment).
And what levels of behavior change occurred? From the figures cited, age of sexual debut and condom use barely changed. And multiple partnership indicators improved a bit, but these were never common enough to explain the almost umprecedented rates of transmission once found in the country. Most of these indicators wouldn't even look out of place in rich countries.
Interestingly, the researchers mention "the Zimbabwean government's early adoption of a home-based care policy [which] may inadvertently have accelerated the process of behavior change. It has been hypothesized that, when people die at home, this direct confrontation with AIDS mortality is more likely to result in a tangible fear of death among family and friends than when patients are primarily cared for in clinical facilities, such as in Botswana"
I'd interpret the effect of this policy rather differently. It could also have taken a lot of HIV positive people out of a health system that was not able to provide people with safe healthcare.
The authors conclude that significant changes in behavior are unlikely to have resulted from increasing levels of mortality alone. They also suggest that prevention programs provided people with information about the link between risky sexual behavior and HIV transmission. And they are probably right, to an extent. But why were these programs so successful in Zimbabwe when they failed so miserably elsewhere? The authors bluster on, unconvincingly.
Indeed, they don't even seem that convinced themselves. They can't really put their finger on anything much so they talk about "cumulative exposure" to prevention messages, as if that wouldn't have happened elsewhere. Similar claims have long been made to "explain" what happened in Uganda. After all, there must be some explanation, and if it has to be about sex this one is as good as any other.
I can understand a whole group of stakeholders churning out answers that would satisfy even a UNAIDS employee about the drivers of HIV. I have met few people who wouldn't say similar things. But I don't believe the authors could look on this this paper as a publishable piece of research. If they are all happy with it, then I am disgusted. Their own research screams for investigation of non-sexual transmission levels, but they carry on regardless.
Monday, November 1, 2010
Are Mathematical Models of Human Sexual Behavior Constructed by Humans?
According to a BBC article, male inmates in a prison in KwaZulu-Natal are asking to be circumcised because they believe it will protect them from HIV. It sounds like they have been seriously misinformed. However prisoners may become infected with HIV, and however they may infect others, it is unlikely to be through heterosexual sex.
Figures for men who have sex with men (MSM) include prison populations in the Kenya Modes of Transmission Survey, so it's hard to tell which contributes more to the epidemic. The overall figure is an estimated 15%. However, it would be difficult to attempt to reduce transmission in these groups without really understanding exactly how transmission occurs.
In prison populations, if other countries are anything to go by, tattooing, forced or voluntary, may well play a significant role. If prisoners receive any invasive medical treatment, this may also play a part. Indeed, the very circumcision operation that is supposed to give them protection from HIV could be carried out under unsterile conditions. Prisoners may thereby increase their risk of being infected with HIV and other blood-borne viruses.
Intravenous drug use may also play a part in African prisons and access to adequate supplies of sterile injecting equipment is unlikely where such practices are forbidden. Condoms are also unlikely to be available on the grounds that sex of any kind is also forbidden.
If, as is often assumed, a large amount of HIV transmission in prisons is through men having sex with men, circumcision is unlikely to give any benefit. Circumcision has never been shown to give protection during anal sex. It might even increase risk of transmission. And circumcision will, of course, have no impact on non-sexual transmission whatsoever. This may seem obvious, but not that much is known about the extent to which HIV transmission is truly sexual, MSM related, non-sexual, etc; this is the case both in and out of prisons in African countries.
The BBC article seems to be unburdened by any research or any attempt at criticism. It's just another titillating article about HIV and its assumed associations with illicit sex. But it is particularly worrying that a health minister has said the prison hospital is overwhelmed. When a hospital is 'overwhelmed', do they cut corners, reuse equipment or take any other risks? The fact that the circumcisions are voluntary will be of little comfort to those who question the wisdom of circumcising as many men as possible because of some very dubious evidence that it reduces HIV transmission.
Despite the unconvincing arguments available for the effectiveness of male circumcision in reducing HIV transmission, the pro-circumcision brigade have produced 'evidence' that the operation will be even more effective than previously estimated. This evidence consists of some mathematical modelling, the likes of which has been used to justify all sorts of things, including the assumption that sexual behavior is responsible for almost all HIV transmission in African countries, though not in non-African countries.
That sounds like a pretty flimsy reason for having an invasive operation that may not work and that may carry more risks than it is expected to avert. But the pro-circumcision brigade is not averse to flimsy reasoning. After all, it's not their penises that are in question. They are not taking any risks themselves and are not considered to be the perpetrators of 'unsafe' sex, carelessly spreading HIV among their fellow Africans.
Interestingly, there is a rare voice of opposition to the mass male circumcision orthodoxy from Miriam Mannak. Unfortunately, Mannak seems to be persuaded by some of the pro-circumcision rhetoric that passes for evidence in the HIV world. But she raises a number of objections to the procedure and employs a rarely found quality in her thinking: compassion. The striking thing about adherents of the circumcision approach and the sexual behavior theory of HIV transmission is that they appear to have no compassion or sense of humanity.
As a result, a lot of HIV 'prevention' programing consists of what amount to punitive measures, designed to control an imagined animalistic attitude towards sex and towards sexual partners that only exist in African countries. Mass male circumcision is just one part of this set of punitive measures. It is likely to be as unsuccessful as previous measures to reduce HIV transmission. If epidemiologists fail to even think of people as people, their mathematical models will continue to be as useless as they have been in the past.
Figures for men who have sex with men (MSM) include prison populations in the Kenya Modes of Transmission Survey, so it's hard to tell which contributes more to the epidemic. The overall figure is an estimated 15%. However, it would be difficult to attempt to reduce transmission in these groups without really understanding exactly how transmission occurs.
In prison populations, if other countries are anything to go by, tattooing, forced or voluntary, may well play a significant role. If prisoners receive any invasive medical treatment, this may also play a part. Indeed, the very circumcision operation that is supposed to give them protection from HIV could be carried out under unsterile conditions. Prisoners may thereby increase their risk of being infected with HIV and other blood-borne viruses.
Intravenous drug use may also play a part in African prisons and access to adequate supplies of sterile injecting equipment is unlikely where such practices are forbidden. Condoms are also unlikely to be available on the grounds that sex of any kind is also forbidden.
If, as is often assumed, a large amount of HIV transmission in prisons is through men having sex with men, circumcision is unlikely to give any benefit. Circumcision has never been shown to give protection during anal sex. It might even increase risk of transmission. And circumcision will, of course, have no impact on non-sexual transmission whatsoever. This may seem obvious, but not that much is known about the extent to which HIV transmission is truly sexual, MSM related, non-sexual, etc; this is the case both in and out of prisons in African countries.
The BBC article seems to be unburdened by any research or any attempt at criticism. It's just another titillating article about HIV and its assumed associations with illicit sex. But it is particularly worrying that a health minister has said the prison hospital is overwhelmed. When a hospital is 'overwhelmed', do they cut corners, reuse equipment or take any other risks? The fact that the circumcisions are voluntary will be of little comfort to those who question the wisdom of circumcising as many men as possible because of some very dubious evidence that it reduces HIV transmission.
Despite the unconvincing arguments available for the effectiveness of male circumcision in reducing HIV transmission, the pro-circumcision brigade have produced 'evidence' that the operation will be even more effective than previously estimated. This evidence consists of some mathematical modelling, the likes of which has been used to justify all sorts of things, including the assumption that sexual behavior is responsible for almost all HIV transmission in African countries, though not in non-African countries.
That sounds like a pretty flimsy reason for having an invasive operation that may not work and that may carry more risks than it is expected to avert. But the pro-circumcision brigade is not averse to flimsy reasoning. After all, it's not their penises that are in question. They are not taking any risks themselves and are not considered to be the perpetrators of 'unsafe' sex, carelessly spreading HIV among their fellow Africans.
Interestingly, there is a rare voice of opposition to the mass male circumcision orthodoxy from Miriam Mannak. Unfortunately, Mannak seems to be persuaded by some of the pro-circumcision rhetoric that passes for evidence in the HIV world. But she raises a number of objections to the procedure and employs a rarely found quality in her thinking: compassion. The striking thing about adherents of the circumcision approach and the sexual behavior theory of HIV transmission is that they appear to have no compassion or sense of humanity.
As a result, a lot of HIV 'prevention' programing consists of what amount to punitive measures, designed to control an imagined animalistic attitude towards sex and towards sexual partners that only exist in African countries. Mass male circumcision is just one part of this set of punitive measures. It is likely to be as unsuccessful as previous measures to reduce HIV transmission. If epidemiologists fail to even think of people as people, their mathematical models will continue to be as useless as they have been in the past.
Subscribe to:
Posts (Atom)
