An overview of the molecular and epidemiological features of HIV-1 infection in two major cities of Bahia state, Brazil

BACKGROUND The high mutation rate of the human immunodeficiency virus (HIV) has created a public health challenge because the use of antiretroviral drugs can generate selective pressure that drives resistance in these viruses.

OBJECTIVE The aim of this work was to characterise the molecular and epidemiological profile of HIV in Bahia, Brazil.

METHODS DNA sequences from regions of HIV gag, pol, and env genes were obtained from previous studies performed in this area between 2002 and 2012. Their genotype and drug-resistance mutations were identified using bioinformatics tools. Clinical and epidemiological data were analysed.

FINDINGS Among 263 individuals (46.4% male), 97.5% were asymptomatic and 49.1% were receiving treatment. Most of the individuals were 31 to 40 years old (36.9%) and infected through heterosexual contact (40.7%). The predominant genotype was B (68.1%) followed by BF recombinants (18.6%). Among the individuals infected with either F or BF genotypes, 68.4% were women and 76.8% were infected through heterosexual transmission. The prevalence of associated mutations conferring antiretroviral resistance was 14.2%, with 3.8% of all mutations conferring resistance to protease inhibitors, 9.43% to nucleoside reverse transcriptase inhibitors, and 8.5% to non-nucleoside reverse transcriptase inhibitors. Drug resistance was higher in individuals receiving treatment (26.1%) than in the drug-naïve (4.3%) individuals.

MAIN CONCLUSIONS This study will contribute to the understanding and monitoring of HIV epidemic in this Brazilian region.

Keywords
HIV subtype; drug resistance; Bahia; genotyping; mutations; epidemiology