PREVENTIONEERS: The Biggest Challenge to HIV Prevention

With every new wave of HIV prevention initiatives comes a lament. The new (and not so new) researchers complain that lives are being lost, efforts are being wasted, and governments and policy makers don’t “get it.”

A recent perspective article published in the New England Journal of Medicine represents the worst of these agony aunt pieces. The authors dwell on the “enormous challenges,” the “staggering loss of life,” and the “repeated failures of biomedical interventions” except of course for that of circumcision, and carry on how we must invest more money, do more research, change the paradigm.

By now, male circumcision has been absorbed into the scientific community’s canon of received wisdom. Yet, the wisdom is really both a desperate hope and an unwillingness to upset the apple cart of fellow researchers. After all, these people rely on each other for support in their pursuit of new projects and funds to carry them out.

Yet this old song and dance reminds me of that age old (and highly localized) symbol of San Francisco. No, not the Golden Gate Bridge. I’m talking about the haggard man on the corner with his hand out, pleading poverty and helplessness, in a city with 27 places serving free food every day of the week, every day of the year. It’s a sympathy play to our most basic instinct for compassion.

Nevertheless, the authors make some important points. First, they point out that artificial end points and speculative estimates of expected infection rates make drawing conclusions exceedingly difficult. Second, they say that poor trial infrastructure results in participant attrition and lack of follow up, further hampering interpretation of data. Thirdly, they complain about the confusion ethical considerations that require providing safer sex education, condoms and follow up have on determining efficacy.

Now, I’m not an epidemiologist. And I’m not a scientist or statistician. But I am someone who makes a living figuring things out. And to my mind, every single one of these issues applies to the circumcision trials. First, the end points were decided by the researchers and supervisory infrastructure entirely arbitrarily based on “ethical considerations” instead of at a biomedical event, as the authors of this article suggest is desirable. These “ethical considerations,” mind you, didn’t seem to bother them at the beginning of the trials.  The small number of infections yielded mildly statistically significant differences at 18 months. However, the question whether those numbers would or wouldn’t close the gap, or even widen over time, will never be answered.

Second, participant attrition was interpreted as enhancing the efficacy despite the fact that the problem of the control group not receiving the same level of traditional prevention interventions (condoms, education, routine medical care providing further opportunity for reinforcement) was never adequately controlled for. If the control group has less contact with study personnel, wouldn’t their attrition rate likely be greater? And if so, how do you factor this in? Follow up was another problem. Has there been any follow up? What do we know about the two groups more than a year after the trials were ended? Very little is the answer because many of the control group were removed therefrom by circumcision; a biomedical event, if you will, that ended any future meaningfulness to follow up.

The third issue is so obvious, so blatant that it hardly needs analysis. Simply put, you cannot adequately separate safer sex messages from the biomedical outcome of circumcision when they are delivered together. This was a problem in a Cambodian microbicide trial that ended in failure, confusion and controversy around the same time.

So what is the answer to HIV/AIDS? It is this. We have prevention technologies that do not involve issues of informed consent, mixed messages (i.e. condoms are still necessary), or complications and botched surgeries where health care infrastructure is lacking or non-existent. They are effective. They are cheap. And they are freely available to enlightened communities. Condoms, encouraging fewer partners and discouraging multiple concurrent partners, frequent testing leading to early detection, and treatment itself. This is not a hard problem on the scientific plane. It is enormously difficult on the political plane, both among governments and scientific organizations because HIV competes with those groups’ professional, economic, and organizational agendas.

Reference

N Engl J Med. 2008 Apr 10;358(15):1543-5. Challenges to HIV prevention–seeking effective measures in the absence of a vaccine. Lagakos SW, Gable AR. Harvard School of Public Health, Boston, USA.

This entry was posted in Medicine and tagged , , , , , , . Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s