Figure 1.

Prevalence of predicted R5 and X4 coreceptor usage. Participants first-sampled within 3 years after EDI harbored mostly R5 usage (light gray bars), but 23 of 102 (22.5%) had detectable X4 variants (dark gray bars). A significant prevalence of X4 usage was detected at all time intervals, even in the first 3 months after infection (18.8%). Abbreviations: EDI, estimated date of infection; R5 usage, viral population demonstrated R5 coreceptor usage; X4 usage, viral population with >1% X4 variants detected at a false positive rate of 5%.