Abstract:
Background: The impact of antiretroviral therapy (ART) on sexual risk behavior and
HIV transmission among HIV-infected persons in Africa is unknown.
Objective: To assess changes in risky sexual behavior and estimated HIV transmission
from HIV-infected adults after 6 months of ART.
Design and methods: A prospective cohort study was performed in rural Uganda.
Between May 2003 and December 2004 a total of 926 HIV-infected adults were
enrolled and followed in a home-based ART program that included prevention
counselling, voluntary counseling and testing (VCT) for cohabitating partners and
condom provision. At baseline and follow-up, participants’ HIV plasma viral load
and partner-specific sexual behaviors were assessed. Risky sex was defined as inconsistent
or no condom use with partners of HIV-negative or unknown serostatus in the
previous 3 months. The rates of risky sex were compared using a Poisson regression
model and transmission risk per partner was estimated, based on established viral loadspecific
transmission rates.
Results: Six months after initiating ART, risky sexual behavior reduced by 70%
[adjusted risk ratio, 0.3; 95% confidence interval (CI), 0.2–0.7; P ¼ 0.0017]. Over
85% of risky sexual acts occurred within married couples. At baseline, median viral
load among those reporting risky sex was 122 500 copies/ml, and at follow-up,
< 50 copies/ml. Estimated risk of HIV transmission from cohort members declined
by 98%, from 45.7 to 0.9 per 1000 person years.
Conclusions: Providing ART, prevention counseling, and partner VCT was associated
with reduced sexual risk behavior and estimated risk of HIV transmission among HIVinfected
Ugandan adults during the first 6 months of therapy. Integrated ART and
prevention programs may reduce HIV transmission in Africa
