Tuesday, August 15, 2006

HIV, Circumcision, and Vaginal Microbicides

I work in HIV prevention. Part of my job is to run drop-in hours at a little storefront in a little town with not much foot traffic. Sometimes, I put out the "open" sign and no one drops in. Then I have to find something useful and relevant to do with my time.

So today I'm being useful by watching a live webcast of the plenary address at the world AIDS conference in Toronto. (See http://www.projectinform.org/.) Dr. Gita Ramjee, a researcher from South Africa just suggested that one element of HIV prevention should be male circumcision. I kid you not. In clinical trials where adult men were randomly assigned to be circumcised or not, acquisition and transmission of HIV was reduced 60% in the circumcised group.

Don't panic! This is only a first clinical trial. No one is proposing implementing mass circumcisions at this time. However there are three additional clinical trials underway, and if they have similar results, we may see such campaigns before long.

Obviously, being uncircumcised does not necessarily put you at high risk of HIV infection. After all one can still use a condom! But in parts of Africa, adult circumcision seems to be more socially acceptable than condom use. Whoa, right? Some guys would rather have their foreskins removed, than use a rubber.

Of course I don't know what kind of "incentives" were offered to the men who took part in this study, or how much of a choice they had. It may be that participating in this clinical trial was the most lucrative job opportunity available to them. That's a whole nother issue. But, still. Whoa.

The researchers like circumcision as a prevention method because it does not rely on "compliance." Condoms are way more effective than circumcision (~98% vs. ~60%) if people use them correctly every time, but that doesn't actually happen. In real life, with typical compliance – that is, with people using condoms imperfectly and only some of the time – their effectiveness is around 85%. That rate comes from U.S. studies, and the rate may be much lower in many parts of Africa, where there are significant cultural barriers and pressures that prevent people from using condoms consistently. (See e.g. http://www.bloomberg.com/apps/news?pid=20601085&sid=a7pqF4l1xg4w&refer=europe, http://www.npr.org/templates/story/story.php?storyId=5548540.)

Nevertheless, I am overwhelmed by the idea of using circumcision, a basically irreversible surgery (and you know I have more to say about circumcision) , as a form of disease prevention. It just seems like this can't be a good first choice. But then, I guess if I lived in a place where 50% of adult women are already infected, as in some communities in sub-Saharan Africa, I might be ready to consider such extreme measures.

And actually, thank goodness, circumcision is not the only hot new prevention method in the works. The researchers at this conference, particularly Dr. Ramjee, are also very big on vaginal microbicides. These are substances like Nonoxynol-9 which, when inserted into the vagina, kill microbes such as HIV and other STIs (sexually transmitted infections). N-9 is actually a horrible microbicide in that it is highly toxic, so much so that it causes vaginal or anal irritation and bleeding and may actually increase the risk of HIV prevention. Don't use it!

So the researchers are now looking at other microbicides that they hope will be less toxic, more HIV-specific (so that they don't disrupt the normal, healthy balance of bacteria and other organisms that live in the vaginal and digestive tracts), not systemically absorbed (that is, they should only affect the part of the body you apply them to), and that do not act as contraceptives (so that women can choose to get pregnant while still reducing their risk of HIV infection). There are many clinical trials with various microbicides being conducted in Southern and Western Africa, in India, and in Philadelphia. I'm thinking cautiously about these medications for now (see my previous post on the new HPV vaccine). Yet, they may offer a relatively safe and effective HIV prevention to people who have few other options, and who are otherwise at appallingly high risk.

For more information on sexual health and HIV/AIDS, check out these web sites:



http://tapestryhealth.org/ (in Western Massachusetts)



And, stay tuned for more thoughts on circumcision.

1 comment:

Obstructing Reality said...

Interesting findings - given the pendulum-like trend in circumcision in the US, I'd wonder if the AMA would use information like this to push universal circumcision (again). Wasn't it only a year ago that they started giving "permission" to not cut again?

Also, don't forget to send me EH's email about heads. :-)