Study flow diagram.

<p>Study flow diagram.</p

Distribution of genotypic drug resistance mutations for patients with virologic failure on second-line ART in a large ART roll-out program in South Africa.

<p>ART: antiretroviral treatment. PI: protease inhibitor. NRTI: nucleoside reverse transcriptase inhibitor. NNRTI: non-nucleoside reverse transcriptase inhibitor.</p>*<p>Thymidine analog mutation.</p>†<p>Mutations at codons L100I, V108I, Y188C, were not detected.</p>§<p>Mutations reducing etravirine susceptibility. Others found in the cohort include V90I, K101E/P, V106I, and V179D. The A98G, L100I, Y181I/V, and M230L mutations were not detected.</p