Detectable Virus Speeds HIV Evolution

Maintaining a low but detectable viral load during highly active antiretroviral therapy is associated with increased evolution of HIV because the immune system has to constantly defend against the virus, according to a study in the April 30 issue of the journal AIDS. Ten of 18 patients studied who had persistent low-level viremia experienced drug treatment failure over a 27-month period, compared with no cases of treatment failure among patients with viral suppression. Researchers suggest that the development of drug-resistant HIV mutations is linked to sustained immune system activation; the HIV-specific T-cell response was 12-fold greater in patients with persistent low-level viremia than in patients with ongoing viral suppression. The researchers recommend patients with detectable viremia be switched to different medications to suppress HIV to undetectable levels.