CROI 2014: New tools to track the epidemic and prevent HIV infections

Abstract

As discussed at the 2014 Conference on Retroviruses and Opportunistic Infections (CROI), substantial advances have been achieved in using laboratory tools to track the leading edge of HIV transmissions globally. Phylogenetic and phylodynamic studies have identified clusters of new infections occurring along geographic routes and in different groups, including young men who have sex with men. New assays for detecting acute HIV infection are promising; however, additional strategies are needed to increase uptake of HIV testing in a number of populations. Globally, people who inject drugs face numerous barriers to accessing HIV prevention and treatment services and are in need of integrated approaches to deliver services, address stigma and discrimination, and reform drug policies. Young women and individuals in serodiscordant relationships continue to be at high risk for HIV acquisition. Injectable hormonal contraception with progestins may increase the risk of HIV infection. Bacterial vaginosis may also increase HIV acquisition and transmission. Additional evidence suggests antiretroviral therapy lowers HIV transmission in serodiscordant couples, but high levels of diagnosis, linkage, retention, and viral suppression are needed to reduce population-level HIV incidence. Several programs evaluating the implementation of preexposure prophylaxis (PrEP) have shown high uptake in the United States and resource-limited settings. As adherence is a crucial determinant of PrEP efficacy, long-acting PrEP agents are promising approaches being tested.

Figure 1.

Population attributable fraction plotted against number needed to treat in the iPrEx (Pre-Exposure Prophylaxis Initiative) trial to identify populations who may benefit the most from preexposure prophylaxis. Dotted line indicates mean number needed to treat. Adapted from Buchbinder et al.