Table 1

Representation of natural history and transmission of HIV and sexually transmitted diseases in the STDSIM simulation of the Uganda HIV epidemic

Transmission probability†Proportion symptomatic
Infection and stageMean duration*M⇒FF⇒MCofactor effect on HIV transmission†‡MF
*Individual stage durations were sampled from a Weibull distribution function with shape parameter 2, except for the duration of the early latent stage of HSV-2 and the interval between recurrent HSV-2 ulcers, which used exponential distribution functions; †per contact; equal for recognized and unrecognized episodes; ‡both for susceptibility (in HIV negative partner) and infectivity (in HIV positive partner); §except during recurrent ulcers.
F, female; M, male; na, not applicable.
    Primary10 weeks0.0450.015nanana
    Asymptomatic5 years0.002250.00075nanana
    Symptomatic pre-AIDS2 years0.002250.00075nanana
    AIDS40 weeks0.011250.00375nanana
    Infectious6 months0.30.210×80%50%
    Latent15 years00nanana
Chancroid10 weeks0.200.1525×90%70%
    Primary ulcer3 weeks0.300.1525×30%
    Early latent (with recurrent ulcers)15 years0.005§0.0025§na§na§na§
    Recurrent ulcer1 week; Interval between ulcers 6 months0.200.1010×15%7.5%
    Late latentLifelong00nanana
GonorrhoeaM 9 weeks; F 13 weeks0.220.1550%20%
ChlamydiaM 12 weeks; F 16 weeks0.200.1230%15%