Improved treatment services significantly reduce the prevalence of sexually transmitted diseases in rural Tanzania: Results of a randomized controlled trial

Objective: To evaluate the impact of improved case management for sexually transmitted diseases (STD) at the primary health care level on the incidence and prevalence of STD. Design: Community-randomized controlled trial. Setting: Mwanza region, Tanzania. Subjects: A random cohort of about 1000 adults aged 15-54 years from each of 12 communities, in six matched pairs. One member of each pair was assigned at random to receive the intervention, and the others served as a comparison community. This cohort was surveyed at baseline and at follow-up 2 years later. About 100 antenatal clinic attenders were also studied in each community on two occasions: the first shortly after the implementation of the intervention, and the second approximately 1 year later. Intervention: Improved services were established for the management of STD, using the syndromic approach, in rural health units. Results: A total of 12 534 individuals were enrolled in the cohort study, of whom 8844 (71%) were seen again 2 years later. The prevalence of serological syphilis (rapid plasma reagin titre greater than or equal to 1:8, Treponema pallidum haemagglutinin assay positive) was 6.2% in both intervention and comparison communities at baseline. At follow-up it was 5.0% in the intervention community and 7.0% in the comparison community [adjusted relative risk (RR), 0.71; 95% confidence interval (CI), 0.54-0.93; P < 0.02]. The prevalence of urethritis in males did not differ significantly between intervention and comparison groups at follow-up, but the prevalence of symptomatic urethritis was reduced by about 50% (adjusted RR, 0.51; 95% CI, 0.24-1.10; P = 0.08). There was no significant difference between the groups in the incidence of self-reported STD symptoms over the last year of the follow-up period, or in the prevalence of any STD in antenatal clinic attenders. Conclusion: The reduction in HIV incidence previously reported in this intervention study can be attributed to a reduction in the duration, and hence the prevalence of symptomatic STD.