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.


3 comments: said...
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Miriam Mannak said...

Hey there,
Thanks for mentioning my post in your blog. I am not persuaded by "the pro-circumcision rhetoric that passes for evidence in the HIV world". I am not an expert you see, so I can't really dismiss what ever claims. That is why on the issues of circumcision an-sich, I decided to be neutral. I do not know the ins and outs. I have my doubts with regards to male circumcision and HIV, as you have noticed.
Thanks again for linking to my blog. All the best,

Simon said...

Hi Miriam
Thank you for your comment. I quite appreciate that the circumcision debate is difficult to follow because it is dominated by vested interests and some very zealous opponents, as you will probably find, having mentioned the subject.

But what you said is quite right, even for circumcision enthusiasts, prison populations are not a particularly useful target. It wHould be far better to improve the conditions, as you have said, that are involved in the spread of HIV and other diseases.

Also, if circumcision does prevent HIV transmission, a very big if, again you're right; those leaving prisons need all the help they can get.

Good luck with the blog, take care.