Changing Trends of HIV, Syphilis, and Hepatitis C among Male Migrant Workers in Chongqing, China: Nine Consecutive Cross-Sectional Surveys, 2010-2018

Background: Male migrant workers (MMWs) have been reported to be vulnerable to human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs). Chongqing, China is one of the major migration destinations and hotspots of HIV. This study aims to explore the prevalence of HIV, syphilis, and hepatitis C virus (HCV), as well as HIV-related knowledge and behaviors, among MMWs in Chongqing. Methods: Questionnaire surveys were conducted, and blood samples were collected and examined among MMWs selected by two-stage stratified sampling in Chongqing from 2010 to 2018. The Cochran-Armitage trend test was conducted to observe the trends in the prevalence of HIV, syphilis, and HCV, as well as HIV-related knowledge and behaviors. The Chi-square test and Binary Logistic Regression were conducted to observe the distinctions between different groups. Results: The overall HIV prevalence was 0.6% with an increasing trend (0.2% to 0.9%, p < 0.001), whereas the overall HCV prevalence was 0.5% with a decreasing trend (0.5% to 0.4%, p < 0.001). The overall syphilis prevalence was 1.3% in the >= 50 age group, 1.0% in the 30-49 age group, and higher than 0.3% in the 16-29 group (X-2 = 19.527, p < 0.001). An uptrend (80.2%-80.6%, p < 0.001) was observed in correct HIV-related knowledge. The 16-29 ((Odds Ratio) OR: 1.575; 95%CI (Confidence Interval): 1.380-1.798; p < 0.001) and 30-49 (OR: 1.697; 95%CI: 1.495-1.926; p < 0.001) age groups had 1.575 and 1.697 times correct HIV-related knowledge more than the >= 50 age group. The proportion of subjects engaged in commercial sex in the past year (7.7%-13.3%, p < 0.001), consistent condom use during this activity (20.5%-54.0%, p < 0.001), and condom use in the last commercial sex (48.6%-72.1%, p = 0.020) were increasing. The risk of engaging in commercial sex in the past year in the 16-29 age group was 0.768 times (OR: 0.768; 95%CI: 0.643-0.917; p = 0.003) less than that in the >= 50 age group. The risk of engaging in non-regular sex in the past year in the 16-29 (OR: 2.819; 95%CI: 2.317-3.431; p < 0.001) and 30-49 (OR: 1.432; 95%CI: 1.184-1.733; p < 0.001) age groups were 2.819 and 1.432 times more than that in the >= 50 age group. The risk of engaging in anal sex in the past year in the 16-29 age group was 6.333 times (OR: 6.333; 95%CI: 1.468-27.327; p < 0.013) more than that in the >= 50 age group. The proportion of consistent condom use during non-regular sex in the past year (10.9%-47.3%, p < 0.001) and condom use in the last non-regular sex (40.8%-71.1%, p < 0.001) increased remarkably. The possibilities of consistent condom use during commercial sex in the past year in the 16-29 (OR: 2.606; 95%CI: 1.847-3.677; p < 0.001) and 30-49 (OR: 1.632; 95%CI: 1.214-2.195; p = 0.001) age groups were 2.606 and 1.632 times more than that in the >= 50 age group. The possibilities of condom use in the last commercial sex in the 16-29 (OR: 1.805; 95%CI: 1.258-2.589; p = 0.001) and 30-49 (OR: 1.360; 95%CI: 1.016-1.821; p = 0.039) age groups were 1.805 and 1.360 times more than that in the >= 50 age group. The possibilities of consistent condom use during non-regular sex in the past year (OR: 1.628; 95%CI: 1.066-2.484; p = 0.024) and condom use in the last non-regular sex (OR: 1.671; 95%CI: 1.148-2.433; p = 0.007) in the 16-29 age group were 1.628 and 1.671 times more than those in the >= 50 age group, respectively. Conclusion: An upward trend of HIV and a downward trend of HCV were observed among MMWs in Chongqing from 2010 to 2018. We also found an increase in commercial sex and inadequate condom use during high-risk behaviors among this population. The overall syphilis prevalence in the middle-aged and elderly groups was higher than in the young group, and elderly MMWs were more likely to engage in unprotected high-risk behaviors. Thus, targeted STI prevention for MMWs in Chongqing, especially those aged 50 years and above, is urgently needed.