Abstract

Background: In a 2008–10 study, we found a pretreatment HIV drug resistance (PDR) prevalence of 18.2% in patients at Bugando Medical Centre (BMC) in Mwanza, Tanzania.

Objectives: To determine the prevalence of PDR and transmitted HIV drug resistance (TDR) in patients visiting the BMC from 2013 to 2015.

Methods: Adult outpatients were sequentially enrolled into two groups, separated by whether they were initiating ART. Previous exposure to antiretroviral drugs, except for prevention of mother-to-child transmission, was an exclusion criterion. HIV pol sequences were analysed according to WHO guidelines for surveillance of PDR and TDR.

Results: Two hundred and thirty-five sequences were analysed (138 ART initiators, 97 non-initiators). The prevalence of PDR was 4.7% (95% CI 2.6%–8.2%) overall, 3.1% (95% CI 1.1%–8.7%) for non-initiators and 5.8% (95% CI 3.0%–11.0%) for ART initiators. PDR to NNRTIs and nucleoside or nucelotide reverse transcriptase inhibitors was found in 3.0% (95% CI 1.5%–6.0%) and 1.7% (95% CI 0.7%–4.3%) of patients, respectively. Resistance to PIs was not observed. The prevalence of TDR was 6.0% (95% CI 3.6%–9.8%).

Conclusions: Prevalence of PDR significantly decreased compared with 2008–10 and was below the WHO-defined threshold for triggering a public health response. National and systematic surveillance is needed to inform Tanzania’s public health strategy.