XVII International AIDS Conference: From Evidence to Action - Clinical and biomedical prevention science.

The question of whether to initiate ART at higher CD4+ cell counts than currently recommended by World Health Organization (WHO) treatment guidelines received much attention at the XVII International AIDS Conference (AIDS 2008). If studies presented at the conference ultimately lead to a revision of WHO treatment guidance, the estimated number of people who will need ART globally will increase substantially. Task-shifting is emerging as an important strategy for dealing with the acute shortage of health care workers in many high-burden countries, and several studies presented at AIDS 2008 demonstrated the impressive health system efficiencies garnered by using nurses or other health care providers to deliver HIV care and treatment. Other key presentations and discussion at the conference focused on the optimal time to start TB treatment in HIV-infected patients, the growing risk of resistance in high-burden countries, including its impact on future treatment options, and several large cohort trials testing optimal drug regimens in resource-limited settings.Biomedical prevention research continues to confirm the long-term, protective benefits of circumcision. Several studies involving HIV serodiscordant heterosexual couples have produced data suggesting a strong protective effect of ART for HIV-negative partners. Disappointing results from recent vaccine and non-ARV based microbicides trials are nevertheless providing important data to this field, and the expanding number of pre-exposure prophylaxis (PrEP) trials and ARV-based microbicides appear to provide the best hope for a new, efficacious biomedical prevention intervention.