Transmitted drug resistance in persons with acute/early HIV-1 in San Francisco, 2002-2009.

Transmitted HIV-1 drug resistance (TDR) is an ongoing public health problem, representing 10-20% of new HIV infections in many geographic areas. TDR usually arises from two main sources: individuals on antiretroviral therapy (ART) who are failing to achieve virologic suppression, and individuals who acquired TDR and transmit it while still ART-naïve. TDR rates can be impacted when novel antiretroviral medications are introduced that allow for greater virologic suppression of source patients. Although several new HIV medications were introduced starting in late 2007, including raltegravir, maraviroc, and etravirine, it is not known whether the prevalence of TDR was subsequently affected in 2008-2009.We performed population sequence genotyping on individuals who were diagnosed with acute or early HIV (