Retrovirus & Opportunistic Infections Part II (cont.)

HIV Transmission

There were several presentations in a symposium that summarized potential strategies for preventing transmission. Dr. Myron Cohen from the University of North Carolina, Chapel Hill, presented on the potential role antiretroviral therapy may have on preventing HIV transmission. He discussed animal data that has shown the potential efficacy of pre- and post-exposure prophylaxis . He talked about studies that are utilizing pre-exposure prophylaxis, as well as recent CDC guidelines for nonoccupational post exposure prophylaxis. He did emphasize the lack of efficacy data and concerns about toxicity and the possibility of selecting for resistance if transmission were to occur. Data was also presented regarding the relationship between antiretroviral therapy and viral load in blood and genital secretions. This discussion focused on how different drugs achieve different levels in the genital tract and how this might be important with regards to the impact antiretroviral therapy may have on HIV transmission.

In the same session there was a presentation given by Dr. Sharon Hillier from the University of Pittsburgh, School of Medicine, and the Magee Women's Hospital in Pennsylvania. She summarized issues unique to women, one of the fastest growing groups with HIV infection around the world. She talked about some of the cultural and social problems faced by women that limit their ability to protect themselves from HIV infection, as well as the importance of them being empowered by the availability of methods that do not rely on the use of the male condoms. This included discussion of the female condom and diaphragm, as well as the development of various agents that might alter vaginal pH in order to reduce infection, as well as the development of antiviral compounds, or so-called 'microbicides'. In fact, she noted that there has been a tremendous amount of interest and research in microbicides development over the last several years with 5 products in 6 large microbicide trials that are anticipated to report results as soon as 2007 or 2008.

There were several important presentations describing issues related to HIV transmission. Dr. Viani and colleagues studied recently infected adolescents in a multicenter adolescent trial network study called 'ATN 022'. These investigators used the detuned assay to identify adolescents that were recently infection, probably within the last 180 days. These individuals were from 15 different cities and were assessed for the presence of virus with any major drug resistant mutation. They showed that approximately 18 percent had evidence of resistance; the majority being resistant to NNRTIs. This is consistent with what has been seen in adult cohorts of recently infected individuals, and emphasizes the importance of looking for drug resistance prior to initiating antiretroviral therapy.