Objectives: This intervention-linked research aimed to (1) rapidly reduce the prevalence of common curable STIs in Angeles City and (2) maintain STI reductions over time.
Methodology: A targeted strategy was employed with a single round of azithromycin presumptive treatment (PT) given to all female sex workers (SW) reached during one month. Preventive and curative services for SWs were strengthened as were outreach efforts and peer education for freelance SWs. Cross-sectional measurements of N.gonorrhoea and C. trachomatis prevalence using urine polymerase chain reaction (PCR) were done prior to PT, one month and six months post-PT, and stratified by type of sex work. Cross-sectional prevalence was also measured among a sample of clients before and after implementation of the interventions.
Results: A total of 1938 SW received PT and 1651 were randomly selected for the assessment surveys during 3 evaluation rounds. PT coverage among those surveyed one month later was 75% for brothel-based (BSW), 63% for street-based (SSW), 50% for registered (RSW) and 79% for guest relations officers (GRO). The prevalence of gonorrhea and/or chlamydial infections at baseline, 1 month post-PT and 6 months post-PT was: brothel-based SW, 52%, 26%, 23%; street-based SW, 41%, 25%, 28%; registered SW, 36%, 26% and 34%; guest relations officers, 22%, 6%, 24%.
The prevalence of gonorrhea and/or chlamydial infections one month after PT declined 50% for BSW, 39% for SSW, 28% for RSW, and 73% for GRO. Six months after PT, prevalence remained 56% lower than baseline for BSW, and 32% lower for SSW, but had returned to baseline levels for the other groups. Factors related to STI decreases at one month included PT coverage, while at six months, access to improved screening services was more important. The prevalence of gonorrhea and/or chlamydial infections among clients of BSW one month post-PT was 28% and declined to 15% six months post-PT.
Conclusion: Significant reductions in prevalence of common curable STIs are possible when effective interventions reach core groups such as sex workers. In Angeles City, a single round of presumptive antibiotic treatment had a short-term impact on STI prevalence that was proportional to coverage. Longer-term maintenance of STI control requires establishment of effective preventive and curative service.