title: Human immunodeficiency virus, syphilis and hepatitis C virus prevalence trends among cross-border migrant Vietnamese female sex workers in Guangxi, China.
abstract: Global literature indicates the burden of human immunodeficiency virus (HIV), syphilis and hepatitis C virus (HCV) has disproportionately affected cross-border migrant female sex workers (FSW). However, few studies reported the HIV risk among Vietnamese FSW at borderline areas in China. We examined five consecutive years of HIV, syphilis, and HCV prevalence and corresponding risk factors among this group in Guangxi Province of China in the current study.
  
  
  
  Demographic and behavioral data as well as test results of blood samples for HIV/syphilis/HCV testing were collected from the annual National Sentinel Surveillance (NSS) from the year of 2010 to 2014. The prevalence trends were first examined by stratified demographic and behavioral status. Predictive models with logistic regression were further employed to identify risk predictors for HIV, syphilis and HCV combined with multiple imputation for missing data as well as restricted cubic splines for key continuous covariates. Moreover, weighted prevalence using the distribution of venue types among all FSW from the NSS survey as the standardized population was also reported.
  
  
  
  The overall prevalence of HIV, syphilis and HCV across the five year period was 3.2 % (95 % CI = 2.1 %,4.3 %), 6.9 % (95 % CI = 5.3 %,8. %), and 2.6 % (95 % CI = 1.6 %,3.6 %), respectively. HIV prevalence changed from 8.2 % (95 % CI = 0.5 %,15.9 %) in 2010 to 1.7 % (95 % CI = 0.4 %,3.0 %) in 2014, and the prevalence decreased notably among FSW who were younger than 25 years old, stayed less than six months, and who participated in the HIV prevention services (P < 0.05). The syphilis prevalence also ranged from 8.2 % (95 % CI = 0.5 %,15.9 %) in 2010 to 3.9 % (95 % CI = 1.9 %,5.9 %) in 2014, and the prevalence remained relatively stable among FSW who reported inconsistent condom use with clients in the past month, those who did not participate in HIV prevention services, and had lower HIV knowledge (P > 0.05). HCV prevalence increased from 0 % in 2010 to 2.2 % (95 % CI = 0.7 %, 3.7 %) in 2014. Multivariable analyses revealed that infection with HCV increased the odds of HIV and syphilis infection. Drug use (aOR = 44.0, 95C % = 16.3,129.5) increased the odds of HCV infection.
  
  
  
  The relatively higher HIV, syphilis and HCV prevalence among Vietnamese FSW compared to their Chinese counterparts sets a challenge for health officials at both sides. To curb the epidemic among the cross-border FSW, preventive action requires bilateral cooperation and action by health authorities of China and Vietnam. A national-level response system should be launched in order to tackle the urgently ever-increasing epidemic.
authors.affiliation: Department of Epidemiology, Vanderbilt University, 2525 West End Ave. Suite 725, Nashville, TN, 37203, USA. chen.zhang.1@vanderbilt.edu.
authors.forename: Chen
authors.initials: C
authors.lastname: Zhang
authors.affiliation: University of South Carolina, Arnold School of Public Health, 915 Greene Street, Room 408, Columbia, SC, 29208, USA.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Epidemiology, Vanderbilt University, 2525 West End Ave. Suite 725, Nashville, TN, 37203, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: University of South Carolina, Arnold School of Public Health, 915 Greene Street, Room 408, Columbia, SC, 29208, USA.
authors.forename: Shan
authors.initials: S
authors.lastname: Qiao
authors.affiliation: Department of HIV/STD Prevention, Guangxi Center for Disease Control and Prevention, Jinzhou Rd., Qingxiu District, Nanning, Guangxi, China.
authors.forename: Yuejiao
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of HIV/STD Prevention, Guangxi Center for Disease Control and Prevention, Jinzhou Rd., Qingxiu District, Nanning, Guangxi, China.
authors.forename: Zhenzhu
authors.initials: Z
authors.lastname: Tang
authors.affiliation: Guangxi Center for Disease Control and Prevention, Jinzhou Rd., Qingxiu District, Nanning, Guangxi, China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Shen
mesh_terms: D000328:Adult; D002681:China / Q000453:epidemiology; D005260:Female; D015658:HIV Infections / Q000453:epidemiology*; D006526:Hepatitis C / Q000453:epidemiology*; D006801:Humans; D015995:Prevalence; D060386:Sex Workers / Q000706:statistics & numerical data*; D013587:Syphilis / Q000453:epidemiology*; D014171:Transients and Migrants / Q000706:statistics & numerical data*; D014744:Vietnam / Q000208:ethnology; D055815:Young Adult