Friday, October 1, 2010

Nosocomial and Iatrogenic HIV Transmission in Kenya

I have mentioned non-sexual HIV transmission, and especially transmission through unsafe health care, on a number of occasions. However, some people have interpreted such phenomena in very different ways. Though I have never claimed it, some people seem to think that I am saying that most HIV transmission in Africans countries is non-sexual. I am not claiming this, only that a lot of HIV transmission could be non-sexual and a lot of the 'evidence' for sexual transmission is being manipulated, even though it points to something other than sexual behavior as being behind very high rates of transmission.

Nor am I claiming that every person who visits a health facility is at the same risk of being infected. Even in countries with very high prevalence of HIV and other blood-borne viruses, this doesn't mean that HIV transmission in health facilities is common. Safety and hygiene may be a priority most of the time. Even if the odd procedure is missed now and again, this doesn't mean someone is likely to be infected through a medical procedure. For a start, equipment used needs to be contaminated. And even then, the probability of being infected might only be a few percent.

Most health professionals may follow guidelines religiously. The worry is when there is a shortage of equipment, a lack of clarity about roles or procedures, a temporary drop in vigilance. The fact that such events don't often occur might make them even less likely to be spotted in time. But even when such things go wrong, they still might not give rise to a high risk of people being infected with HIV or anything else. It depends on many circumstances.

I argued recently that sexual transmission of HIV, being quite inefficient, cannot give rise to infections quickly enough or in high enough numbers to explain very serious HIV epidemics like those found in many Southern African countries, or even those found in East Africa and other countries with medium epidemics. I used the terms 'Mediocristan' and 'Extremistan' from Nassim Nicholas Taleb's book The Black Swan and suggested that sexual transmission of HIV is a phenomenon of Mediocristan but that transmission in health facilities is from the realm of Extremistan.

In other words, medical transmission of HIV may not happen all the time, it may not even happen very much. But when it happens, it can affect large numbers of people. Some events may not affect many people, they may just peter out without anyone noticing. Perhaps a few infections will be found, of HIV, hepatitis or something else. But they may never be identified as medically transmitted. This sort of event is still one of Mediocristan. But if the conditions are right and some unsafe procedure results in HIV being transmitted, the number infected could be very high. Inordinately high rates of transmission are possible in health settings that are not possible through unsafe sexual behavior, no matter how much of it may take place.

There have been quite a number of documented (though mainly uninvestigated) outbreaks of HIV that have taken place in medical facilities. These have taken place in both rich and poor countries. The only difference is that in rich countries it is possible to recall and attend to tens of thousands of people. And the risk of infection is not too high if HIV and prevalence of other blood-borne diseases is low in the population. But in poor countries, even if the possibility of an outbreak is noticed, it is unlikely that their health services will have the capacity to investigate, let alone identify all those infected.

So, I am not saying that most HIV infections in Kenya, for example, come from some kind of medical treatment, possibly unsafe injections. I'm saying that in a medium prevalence epidemic, such as Kenya's, some non-sexual transmission must have occurred, especially in areas like Nyanza. There, prevalence is exceptionally high among members of the Luo tribe. Also Western province, where prevalence is exceptionally high among Luhya women. There are probably still plenty of medical transmission events occurring and, if not, there probably will be some in the future.

In countries with the highest HIV transmission rates, such as Swaziland, Zimbabwe, Namibia, Botswana, South Africa and others, medical transmission is likely to contribute a far bigger proportion of infections than in lower prevalence countries. Access to health services is also quite high in these countries. But some of the lower prevalence countries, such as those in East Africa, have lower levels of health services, accessible to far fewer people. And there are many low prevalence areas that also have low access to health services and high prevalence areas with high access to health services. So this connection, if it really is a connection, needs to be investigated.

There are other non-sexual risks relating to HIV transmission, such as through cosmetic practices, head, face and body shaving, manicure, pedicure, tattooing and others. These probably happen, but the question of how often is an empirical one. In countries where most people don't attend medical facilities very much, an epidemic could bump along at a relatively low prevalence for years, much as it has done in Kenya, Uganda, Tanzania and various other countries, with all modes of transmission contributing a steady proportion.

An increase in medically transmitted infections could have quite a profound impact on prevalence, but there's no reason why such an outbreak should be noticed. Or rather, the effects of the outbreak might only be noticed little by little and might not seem like an event with a single, identifiable cause. Especially if no one is looking for the cause or they assume there was a sudden spike in 'unsafe' sexual activity, the extent of which surpasses credibility, if anyone was worried about what is and is not credible about African sexuality.

This is why I have drawn attention to the comments of the Kenyan Medical Services Minister, Professor Anyang' Nyong'o. He has alluded to the state of Kenya's health services, shortages of personnel, overuse of injections, unsafe practices and the consequent risks of nosocomial transmission of HIV, hepatitis and other blood-borne diseases. Now that the country is aware of this risk, it's time to take steps to improve safety in health facilities and rethink the approach to HIV that limits itself to lecturing people about what they should and shouldn't do in their private lives. People need to be aware of the serious non-sexual risks that exist and they should be made aware of how to avoid such risks.

The yearly rate of new HIV transmissions in Kenya may presently be low. Sexual transmission, I would argue, is always low; cosmetic and other practices may also contribute very little. But in a country with health service provision as poor as Kenya's, it's only a matter of time before a significant outbreak occurs. Some significant outbreaks may have already occurred, surveillance is far to low to detect such an event. Unless UNAIDS and others with control of finance and policy are prepared to, like Minister Nyong'o, accept that nosocomial transmission takes place, has always taken place, and will continue to take place, HIV epidemics in African countries will never be reduced, let alone eradicated.


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