Impact of HIV Counselling and Testing on HIV Seroconversion and Reported STD Incidence Among Male Factory Workers in Harare, Zimbabwe

Objectives: To assess the impact of HIV counselling and testing on HIV seroconversion and incidence of reported sexually transmitted diseases (STDs) among male factory workers in Harare, Zimbabwe.

Design: Prospective, observational study among men recruited to participate in a future workplace based AIDS prevention intervention.

Methods: Participants provided STD histories and blood for HIV antibody testing at enrolment and six month intervals during visits to factories. Participants received HIV test results, post test counselling, and free STD services at the project clinic.

Results: Between March 1993 and June 1995, 2,414 men were enrolled with 85% follow up. Overall HIV sero-incidence was 2.60 per 100 person-years; the incidence of reported STDs was 10.19 per 100 person-years. Men who obtained their HIV test results had significantly higher HIV sero-incidence and incidence of reported STDs compared to men who did not obtain their results (IRRs: 1.87, 3.47, respectively). Among men who obtained their HIV test results, a non-significant 40% decrease in HIV sero-incidence was observed after obtaining test results compared to before obtaining results (p = 0.18). The incidence of reported STDs, however, increased by 30% after obtaining HIV test results (p = 0.10).

Conclusions: Decreased HIV sero-incidence in the face of increased reported STD incidence suggests that timely treatment of STDs may decrease the risk of acquiring HIV even in the absence of behaviour change. In populations with high rates of HIV and STDs, the greatest benefit of HIV counselling and testing may be achieved by simultaneously offering STD screening and treatment services.