Multiple logistic regression showed that a low CD4 T-lymphocyte count (≤200 cells/mm3) at diagnosis (adjOR 14.2, 95% CI: 3.1-64.5), a history of opportunistic infections (adjOR 3.5, 95% CI: 1.9-6.4), and late entry into an HIV program after diagnosis (>1 year) (adjOR 9.2, 95% CI: 3.8-22.2) significantly increased the odds of virologic failure in the study population. This evidence concerns the gene CD4 and Opportunistic infection.