Frequency and diversity of human immunodeficiency virus type 1 mutations associated with antiretroviral resistance among patients from Southern Brazil failing highly active antiretroviral therapy (HAART).

The human immunodeficiency virus type 1 (HIV-1) epidemic in Brazil is spreading to small municipalities as well as the innermost parts of the country and scarce information has been reported on the frequency of HIV-1 resistance-associated mutations in these areas. To determine the frequency and diversity of the HIV-1 antiretroviral resistance-associated mutations among patients failing highly active antiretroviral therapy from Londrina in Southern Brazil, 127 HIV-1 genotyping tests that were assayed during January 2000 to July 2008 from 108 patients were evaluated. Sixty-nine patients (63.