National HIV Drug Resistance Survey - Tanzania

Tanzania's antiretroviral-therapy programme has achieved major scale, and strong viral suppression is one of its most important successes. Drug-resistance surveillance asks the question that follows from that success: among the smaller group of people whose virus remains unsuppressed, what resistance patterns are present, and what do those patterns mean for protecting treatment effectiveness over time?

The National HIV Drug Resistance Survey was designed to answer that question at national scale. It combines probability-based sampling of people receiving antiretroviral therapy with viral-load testing and genotyping among those meeting criteria for resistance analysis. The design allows the programme to describe overall suppression while looking more closely at the patients for whom treatment is not achieving the desired virological response.

This creates an important interpretive balance. High population-level success and targeted vulnerability can both be true. Resistance findings among people with high viraemia should not be generalized to everyone receiving treatment, yet they are valuable precisely because they can reveal small signals before they grow into wider programme threats. Linked analyses have examined adolescents and young adults, emerging integrase-inhibitor resistance and viral suppression in the dolutegravir era. Together, they position surveillance as a tool for programme resilience: celebrate effective treatment, identify groups needing closer attention and retain the laboratory and analytic capacity to detect changes that may influence future regimen strategy, adherence support and monitoring.