Fig. 5.

HIV-1 past population dynamics in North America (green) and Thailand (gray). Plots were built using the env gene and the Bayesian Skyline Plot model. The analyses primarily revealed that genetic diversity (thick lines) has remained high through time despite the number of AIDS cases (thin lines) dropping considerably and thatHIV was circulating years before the first AIDS cases were detected. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)