Surveillance of HIV-1 drug resistance in Tanzania across the pre- and post-dolutegravir eras: A systematic review and meta-analysis

This systematic review and meta-analysis assessed the prevalence, mutation patterns, and factors associated with HIV drug resistance (HIVDR) in Tanzania. We searched PubMed/MEDLINE and Embase from January 1, 2006, to June 17, 2025, and included 26 eligible studies reporting 1604 genotypic data. Using a random-effect model, the pooled prevalence of any HIVDR-associated mutation (AM) was 60.6% (95%CI:50.7-70.5%), rising to 65.5% (95%CI:51.1-79.9%) among individuals with viral load≥ 1000 copies/mL. Treatment-naïve and treatment-experienced individuals exhibited 29.2% and 68.5% HIVDR-AM, respectively. Children under 15 years had the highest HIVDR-AM prevalence of 70.0%. Of 4018 mutations identified, 41.2% conferred resistance to nucleoside reverse transcriptase inhibitors (NRTIs), 38.6% to non-NRTIs, 18.4% to protease inhibitors, and 1.7% against integrase strand transfer inhibitors (INSTIs). The high burden of HIVDR-AM affecting six in ten people living with HIV supports ongoing roll-out of dolutegravir-based regimens to mitigate the widespread reverse-transcriptase resistance in Tanzania. Although still uncommon, emerging INSTI resistance is concerning, underscoring the need for strengthened surveillance and targeted HIVDR prevention strategies.