The incubation and duration of acute retroviral syndrome (ARS) have been associated with progression to AIDS. We assessed the independent effect of specific symptoms at ARS on the rate of progression to AIDS or a CD4+ count of <200 cells/mm3 in 70 ARS patients. The incubation and duration of ARS features were stratified on their medians. The Cox regression model was used to calculate the adjusted relative hazard (ARH) of progression. Short incubations of fever (ARH = 5.8, P = 0.004), fatigue (ARH = 2.7, P = 0.06), and myalgia (ARH = 3.8, P = 0.04) were associated with faster disease progression, as was the long duration of most symptoms (ARH range: 3.1-8.1, P < 0.03 to P < 0.001). Pathogenetic mechanisms involved in the incubation of ARS features may be associated with progression to AIDS.