Friday January 27, 2012
I was very amused when my editor sent me a link to an article about the CDC's recent
report on the overall reduction in
HIV risk behaviors among households in the United States in an e-mail with the subject line "You've had an impact!" He certainly knows how to make a sex educator feel good - even if he was mostly teasing.
In any event, the study is an interesting read. The overall percentage of people engaging in risky behaviors - including exchanging sex for drugs or money, having more than 5 sexual partners in a year, and engaging in unprotected sex - dropped significantly for both genders between 2002 and 2006-10, and the number of people seeking STD treatment (which can reduce the risk of HIV) went up. However, there is still room for improvement.
Furthermore, one of the other factors that came up in the CDC report is the significant racial differences in risk profiles - for example the percentage of African American men who have had five or more opposite sex partners in the previous year is substantially higher than seen in other racial groups. It's a good reminder that there are many factors which influence individual's HIV risk, including community behavioral norms.
Wednesday January 25, 2012
In the February 1st issue of the Journal of Infectious Diseases, scientists from the University of Washington published a study that further illustrates the potential importance of antiretroviral therapy in preventing HIV. The study of discordant couples found that one of the most important factors in predicting the likelihood of HIV transmission was viral load. As the amount of HIV in the blood increased, so did the risk of transmission during any sexual act. This explains how, and why, antiretroviral treatment could reduce a person's infectivity - the "treatment as prevention" paradigm.
The study also confirmed several other factors that are important for prevention. The scientists found that condom use was highly effective at preventing HIV. They found that genital ulcer diseases such as genital herpes increased the likelihood of transmission. They also confirmed the protective role of circumcision.
Interestingly, one unexpected result of the study was that the increased risk of transmission from men to women, as opposed to vice versa, could largely be explained by other factors - such as viral load. This flies in the face of the historical understanding that the widely observed difference was primarily due to the mechanics of exposure during sex. Men deliver a large load of potentially infected material (semen) into the vagina, where women have a large area of cells which are susceptible to infection. In contrast, women's vaginal secretions are primarily infectious to men through a much smaller surface area on the penis, and they are more easily removed after sex. It will be interesting to see if that result is borne out in further studies or if it turns out to be a fluke.
Monday January 23, 2012
I've written about the problems with the
30 day testing rule for actors in pornographic films, and I have strong feelings about the importance of
using barriers as well. That's why I was moderately glad to see that Los Angeles recently enacted
legislation requiring adult film actors to wear condoms on shoots where sexual intercourse takes place.
Is the legislation perfect? Of course not. Is it better than nothing? Probably - assuming that it doesn't drive adult film companies to areas where there isn't any regulation at all. I honestly can't evaluate how likely that is. Some people say it won't happen, others say that the companies will flee. Still, it would be great if there was more porn available that featured individuals practicing safer sex. Mind you, if people really want to practice safer sex, condoms during vaginal and anal intercourse aren't enough. There's also the question of oral sex....
Friday January 20, 2012
The American Cancer Society recently released cancer statistics for 2011, and overall the numbers were pretty positive. Cancer death rates continued to decline for most of the major killers - including lung, breast, and prostate cancer. However, there were a few outliers - one of which was
oral cancers caused by HPV. The rate of these cancers has been consistently on the rise for the past few years - particularly in young, white men. The risk is thought to be due to HPV transmission during
oral sex, something which can be reduced through appropriate use of barriers during
fellatio and
cunnilingus.