O19.3\u2005Partner services for gonorrhea can decrease new HIV among MSM in king county, washington: a mathematical modeling study

Abstract

Background Partner services (PS) for bacterial STIs has potential to increase STI treatment among infected sex partners and HIV testing among people diagnosed with STIs and their partners. The population-level impact of PS on gonorrhea and HIV incidence has not been estimated. Methods Calibrated to King County’s MSM population, our compartmental gonorrhea-HIV coinfection model captures sexual mixing, gonorrhea and HIV transmission, and scale-up of antiretroviral therapy (ART), pre-exposure prophylaxis (PrEP), and routine STI screening. We assessed incremental impact of PS over 5 and 20 years, and compared gonorrhea and HIV incidence and prevalence without PS, with PS, and with PS that integrates promotion of HIV testing (PS+HIV). In the absence of PS, we assumed that 10%, 10%, and 95% of rectal, pharyngeal, and urethral gonorrhea were treated and 63% of MSM receiving gonorrhea treatment also received HIV testing. With PS, 40% of treated cases received PS, increasing the proportion of partners treated for gonorrhea and tested for HIV by 4%, 4%, and 38% at each site. PS+HIV increased the proportion of gonorrhea-infected MSM tested for HIV to 83%. Results After 5 and 20 years, PS modestly changed rectal, pharyngeal, and urethral gonorrhea incidence and prevalence (<7%). After 5 years, HIV prevalence decreased 0.1% with PS and 0.5% with PS+HIV. HIV incidence decreased 6.0% (from 187.1 to 176.0 per 100,000 persons) with PS and 14.7% (187.1 to 159.6/100,000) with PS+HIV. After 20 years, HIV prevalence decreased 3.2% with PS and 5.6% with PS+HIV. PS reduced incidence 23.3% (75.2 to 57.7/100,000) and PS+HIV 37.7% (75.2 to 46.9/100,000). Conclusion Moderate gonorrhea PS coverage had modest impact on gonorrhea, given high rates of STI testing and treatment in King County. However, long-term PS+HIV increased HIV testing opportunities and substantially reduced HIV incidence. PS+HIV is a potential approach for prioritizing HIV testing in high ART and PrEP coverage settings. Disclosure No significant relationships.