[Studies on behavior change and related factors among female sex workers in Qingdao city of Shandong province, between 2006 and 2015].

This study aimed to analyze the behavior change and related factors regarding HIV/STD epidemics among female sex workers (FSWs) in Qingdao city. According to the requirements set by the"National HIV/AIDS sentinel surveillance program", information on demographics, sexual and drug use behaviors, and HIV-related services among female sex workers (FSWs) was collected from ten consecutive annual cross-sectional surveys from 2006 to 2015. Blood samples were drawn for serological tests on both HIV and syphilis antibodies. Data from the sampled FSWs over the ten years, a higher proportion of participants who were aged 30 or more, married or cohabited and on-call FSW were followed. The prevalence of syphilis increased significantly from 1.0% (4/420) in 2006 to 13.3% (53/400) in 2015 (trend (2)=54.22, <0.001). Rates on illicit drug use were ranging from 12.0% (48/400) and 55.5% (222/400) while the rate on consistent condom use with clients in the last month showed decreasing, with trend (2)=170.62, <0.001. The proportion of HIV-related knowledge score ≥6 (trend (2)=152.96, <0.001), or ever been tested for HIV (trend (2)=114.87, <0.001) were both significantly increased over the last ten years. Between 2009 and 2015, results from the annual stratified analysis showed that the FSWs who used drugs were more likely than the FSWs who were non-drug users less consistently using condoms with clients in last month and being syphilis positive (<0.05). On-call FSWs were more likely to be syphilis positive (<0.05) than the non on-call FSWs. The prevalence of syphilis among FSWs in Qingdao city had been rising over the last ten years, with synthetic drug abuse as an important risk factor. Better targeted surveillance and intervention efforts among those drug-using FSWs seemed important to reduce the epidemics.