HIV-1 and Syphilis Prevalence Among Local Chinese and Cross-Border Migrant Female Sex Workers in Sino-Vietnam Border Cities in Guangxi, China: A Nine-Year Consecutive Cross-Sectional Study

Abstract Background To analyze the trends of HIV-1 and syphilis prevalence as well as associated factors among local Chinese female sex workers (LCFSWs) and cross-border migrant female sex workers (CMFSWs) in Sino-Vietnam border cities in Guangxi, China. Methods A consecutive cross-sectional study was conducted from 2010 to 2018 in three border cities in Guangxi. The survey was conducted through face-to-face interview with a structured questionnaire. HIV-1 and syphilis infections were tested simultaneously. Cochran-Armitage analysis was used to assess the trends of HIV-1, syphilis and HCV prevalence, as well as the trend of risk behaviors, HIV/AIDS knowledge and prevention services. Multivariate logistics regression analysis was used to identify factors associated with HIV-1 and syphilis infection.Results Totally, 19873 LCFSWs and 1723 CMFSWs were enrolled. The overall prevalence of HIV-1 and syphilis infection was 0.91% and 5.14%, respectively. The HIV-1 prevalence among CMFSWs was higher than that among LCFSWs, without a declined trend. However, a downward trend was observed among LCFSWs. Overall, the main associated factors of HIV-1 infection among CMFSWs shifted from age >35 years old, staying in current residence for >12 months, self-reporting of STIs in the last year during 2010-2015 to inconsistent condoms use in commercial sex in the past month, HCV infection, self-reporting of STIs in the last year during 2016-2018. The main correlated factors of syphilis infection among CMFSWs changed from staying in current residence for 6~12 months, self-reporting of STIs in the last year, HCV infection during 2010-2015 to low-tier working venues, self-reporting of STIs in the last year, sexing with commercial male clients who used aphrodisiac drugs during 2016-2018. For LCFSWs, the relative strong associated factors of HIV-1 infection shifted from primary school or illiterate education background, illicit drugs use during 2010-2015 to the marital status of unmarried/divorced/widowed, sexing with commercial male clients who use aphrodisiac drugs during 2016-2018, while the main factors of syphilis infection changed from self-reporting of STIs in the last year, illicit drug use during 2010-2015 to self-reporting of STIs in the last year, HCV infection during 2016-2018.Conclusions The relatively higher prevalence of HIV-1 infection and frequent risk behaviours among CMFSWs in border cities in Guangxi, indicating that CMFSWs is the high-risk population for HIV-1 infection and transmission in the region, and is the key population of HIV/AIDS prevention and control. Meanwhile, the change of HIV infection-associated risk factors over time suggests that HIV intervention strategies need to be changed accordingly.