Guixiang Wang

HIV prevalence and risk behaviors among male clients of female sex workers in Yunnan, China

Objectives:To assess the prevalence and risk factors of HIV among male clients of female sex workers (FSWs) in China. Methods:Convenience sampling methods were used to recruit 315 clients using FSW-client and client-client networks. Subjects provided information on sociodemographic characteristics and sexual and drug behavior patterns. Blood samples were collected for HIV testing and urine samples for opiate testing. Results:Overall HIV prevalence was 6.0%; among drug users, it was 30.8%. 33.7% of respondents reported that they always use condoms in commercial sex and 63.5% that they used a condom in the last commercial sex episode. Drug use (OR: 6.1; 95% CI: 1.7 to 21.4) and lack of a regular sexual partner (OR: 6.3; 95% CI: 1.8 to 21.9) were significantly associated with HIV infection. Conclusions:Clients of FSWs serve as potential bridges for HIV transmission from the high-risk FSWs to the low-risk general population, making them a key target for intervention. High HIV prevalence rates among clients in Kaiyuan is particularly alarming given their risk behavior patterns including high rates of partner exchange, low condom use rates, and drug-using behaviors. Innovative interventions are needed to reduce the risk of HIV among clients and reduce the bridge of transmission to the general population.

Prevalence and predictors of herpes simplex virus type 2 infection among female sex workers in Yunnan Province, China

Summary: The objective of this study was to determine the seroprevalence of herpes simplex virus type 2 (HSV-2), and to evaluate the relationship between HSV-2 infection and sociodemographic factors and the sexual practices of female sex workers (FSWs) in Kaiyuan city, Yunnan Province, China. This cross-sectional study involved 737 FSWs and was carried out from March to May 2006 with confidential interviews and laboratory tests for HSV-2 and other sexually transmitted infections (STI). HSV-2 was the most common STI (68%), followed by Chlamydia trachomatis (26%), Trichomonas vaginalis (11%), Neisseria gonorrhoeae (8%) and syphilis (7%). Prevalence of HIV-1 was 10.3%. Adjusted odds ratios of HSV-2 seroprevalence were 2.6 (95% CI [confidence interval]: 1.30-5.38) for HIV-1 infection, 2.0 (95% CI: 1.33-3.16) for vaginal douching, 2.0 (95% CI: 0.45-0.86) for condom breaking or falling off during sexual intercourse with the client in the previous week, 1.8 (95% CI: 1.07-3.18) for ≥5 years of commercial sex work, 1.6 (95% CI: 1.08-2.33) for ≥5 clients in the previous week, 0.6 (95% CI: 0.45-0.86) for ≥9 years of education. This study identifies a very high prevalence of HSV-2 infections among FSWs in Yunnan Province, with only a few who reported a prior history of genital herpes. HSV-2 serological screening and suppressive therapy should be considered for study populations. Education on the importance of diagnosis, treatment and prevention may help control the spread of HSV-2 infection.

Factors Associated With HIV Testing History and HIV-Test Result Follow-up Among Female Sex Workers in Two Cities in Yunnan, China

Background: The majority of people living with HIV/AIDS in China are unaware of their serostatus, and increasing the utilization of HIV testing may help to control the epidemic. Methods: This longitudinal study was conducted among female sex workers (FSWs) in 2 cities in Yunnan Province, China. Participants were surveyed in face-to-face interviews and tested for HIV and STDs. Factors associated with HIV-testing history and HIV-test follow-up were analyzed. Results: Of the 1642 study participants, 291 (17.7%) had been previously tested and 868 (52.9%) returned for post-test follow-up. Factors associated with having a previous HIV test included attending the Kaiyuan study (aOR: 4.9, 95% CI: 2.3–10.1), ≥9 years of schooling (aOR: 10.9, 95% CI: 2.6–45.5), <5 clients in the recent week (aOR: 1.7, 95% CI: 1.2–2.3), having a regular sexual partner (aOR: 1.9, 95% CI: 1.4–2.5), illegal drug use history (aOR: 2.2, 95% CI: 1.5–3.1), pelvic pain in the past 12 months (aOR: 1.9, 95% CI: 1.1–3.6), HIV-seropositivity (aOR: 1.8, 95% CI: 1.2–2.8), and high perception of HIV risk (aOR: 1.5, 95% CI: 1.1–2.2). FSWs who had ≥9 years of schooling (aOR: 1.4, 95% CI: 1.1–1.9), had <5 clients in the recent week (aOR: 1.3, 95% CI: 1.1–1.6), or were from another province (aOR: 1.9, 95% CI: 1.4–2.5) or city (aOR: 1.4, 95% CI: 1.1–1.8) were more likely to follow-up. Conclusions: The low HIV-testing history and follow-up rates found in this is study is a significant public health problem as many high-risk individuals are not aware of their serostatus. Immediate action needs to be taken to increase the utilization of HIV testing services and notify people of their HIV status.

Prevalence and risk behaviours for Chlamydia trachomatis and Neisseria gonorrhoeae infection among female sex workers in an HIV/AIDS high-risk area

The objectives of this study were to estimate the prevalence of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infection among female sex workers (FSWs) in an HIV/AIDS high-risk area in China and to examine risk factors associated with CT or NG infection. A cross-sectional study of 568 FSWs was conducted in Kaiyuan City, Yunnan Province, PR China. The prevalence rates of HIV, CT and NG in the study participants were 11.1%, 17.4% and 8.3%, respectively. More than one-fifth (21.3%) of participants tested positive for either CT or NG. This study identifies a relatively high prevalence of CT or NG infection among FSWs in Kaiyuan. Notably, HIV infection was found to be associated with NG infection and study participants who tested positive for NG had a higher rate of CT infection. Further studies are warranted to examine the prevalence and spread of CT and NG in China, and their potential impact on the HIV epidemic.

Application of the BED capture enzyme immunoassay for HIV incidence estimation among female sex workers in Kaiyuan City, China, 2006–2007

OBJECTIVE To estimate HIV incidence among female sex workers (FSWs) by serial cross-sectional surveys and IgG-capture BED-enzyme immunoassay (BED-CEIA). METHODS We conducted three cross-sectional surveys, 6 months apart, among all consenting FSWs in Kaiyuan City, China. HIV antibody-positive samples were also tested by BED-CEIA. RESULTS Among 1412 unique participants, 475 tested HIV-negative and attended >1 survey (longitudinal cohort). Compared to 786 HIV-negative FSWs who only participated once, the longitudinal cohort reported more illicit drug use (10.9% vs. 7.4%, p=0.03), injected drugs more often in the previous 3 months (8.8% vs. 5.3%, p=0.02), and had more positive urine opiate tests (13.7% vs. 8.9%, p=0.008). Four participants in the longitudinal cohort seroconverted over the year, with an overall incidence of 1.1/100 person-years (95% confidence interval (CI) 0.3-2.8). Crude BED-CEIA incidence was 3.4/100 person-years (95% CI 2.3-4.4) with adjusted rates similar to the cohort incidence: McDougal, 1.5/100 person-years (95% CI 1.0-2.0); Hargrove, 1.6/100 person-years (95% CI 1.1-2.1). The BED-CEIA false-positive rate was 4.4% (10/229) among samples from FSWs known to be infected > or =365 days. CONCLUSIONS Although limited by power, this study provides additional data towards validating BED-CEIA in China. If confirmed by other studies, BED-CEIA will be a useful tool to estimate HIV incidence rates and trends.

Associations between drug use and risk behaviours for HIV and sexually transmitted infections among female sex workers in Yunnan, China.

This is a cross-sectional study of 399 subjects conducted to explore the association between drug use and risk behaviour for HIV and sexually transmitted infections (STIs) among female sex workers (FSWs), and also to study the prevalence of HIV/STIs among drug-using FSWs (DUFSWs) and non-DUFSWs in Yunnan province of China. Demographic information, mobility, sexual and drug-using behaviours were collected and subjects were tested for HIV/STIs. Mean age was 27 years (SD = ±7.8) and 94 (23.6%) tested positive for recent opiate use. Compared with non-DUFSWs, DUFSWs had a significantly higher prevalence of HIV (38% versus 4%, P ≤ 0.001), herpes simplex virus type 2 (HSV-2; 92% versus 60%, P ≤ 0.001) and STIs (95.7% versus 69.2%, P ≤ 0.001). DUFSWs had a significantly longer duration of commercial sex work compared with non-DUFSWs (median 5 versus 1 years, P ≤ 0.001), and had at least two clients in the last working day. DUFSWs were also more likely to work in low-end commercial sex venues and frequented a greater number of work locations than non-DUFSWs. Compared with non-DUFSWs, DUFSWs were more likely to exhibit riskier sexual behaviours and greater workplace mobility. Interventions targeting drug-related behavioural changes are needed urgently in this population in order to reduce rates of HIV and STIs.

Knowledge of HIV seropositivity is a predictor for initiation of illicit drug use: incidence of drug use initiation among female sex workers in a high HIV-prevalence area of China.

BACKGROUND Drug use and sex work have had facilitative roles in the transmission of HIV/AIDS in China. Stopping drug use among sex workers may help to control the growth of the HIV/AIDS epidemic among Chinese sex workers. METHODS From March 2006 to November 2009, female sex workers (FSW) in Kaiyuan City, Yunnan, China were recruited into an open cohort study. Participants were interviewed and tested for drug use and HIV/sexually transmitted infection (STI) prevalence. Follow-up surveys were conducted every six months. Multivariate Cox proportional hazards regression model with time dependent variables was used to measure the associations between independent variables and drug initiation. RESULTS During the course of the study, 66 (8.8%) FSWs initiated drug use yielding an overall incidence of 6.0 per 100 person years (PY) (95% confidence interval [CI], 4.67-7.58). In the multivariate Cox proportional hazards regression model, being HIV-positive and aware of positive serostatus (adjusted hazard ratio [AHR] 2.6, 95% CI 1.24-5.55), age at initiation of commercial sex work <20 years (AHR 1.8, 95% CI 1.12-3.01), and working in a high-risk establishment (AHR 1.9, 95% CI 1.14-3.04) were associated with illicit drug initiation. CONCLUSIONS Being HIV-positive and aware of positive serostatus was the most salient predictor for the initiation of illicit drug use. Interventions offering sources of education, treatment, support, and counseling to HIV-positive FSWs need to be implemented in order to help promote self-efficacy and safe behaviors among this group of high-risk women.

Prevalence, incidence, and persistence of syphilis infection in female sex workers in a Chinese province

The studys objectives were to investigate the prevalence, incidence, persistence, and associated risk factors of syphilis in female sex workers (FSWs) in Kaiyuan City, Yunnan, China. Three serial cross-sectional surveys were conducted and biological specimens were collected and tested for HIV, sexually transmitted infections, and drug use. The logistic Generalized Estimating Equation regression model was used to identify risk factors for prevalent syphilis. The prevalence of syphilis was 7·5%, 8·4% and 8·8%, respectively, in the three survey periods. Estimated syphilis incidence was 1·07 cases/100 person-years, and the persistence of syphilis per person at 6 months was 90·4%. In multivariate analysis, the factors associated with syphilis were age, lower education level, number of clients in a week, inconsistent condom use with clients, herpes simplex virus type 2 (HSV-2), and Chlamydia trachomatis. Persistent syphilis in this population of FSWs is a serious public health concern.

Association Between Testing for Human Immunodeficiency Virus and Changes in Risk Behaviors Among Injecting Drug Users in Southern China

Background: There is growing need for research in China regarding posttest risk behavior differences among injecting drug users that explores the effect of various testing modes (nonvoluntary vs. voluntary) and other related factors on changes in posttest risk behaviors. Methods: One hundred seventy-two study subjects self-reported human immunodeficiency virus (HIV)-related personal risk behaviors including condom use rates and needle-sharing habits. Fisher exact test and multivariate regression analysis compared the impact of HIV testing mode on ongoing risk behaviors for HIV transmission. Results: The study found that those who received positive test results were 5.37 times more likely to increase condom use with regular sexual partners, that men were 8.8 times more likely than women to increase posttest condom use in commercial sexual activities. Needle-sharing behavior was significantly lower for subjects who tested HIV-positive (odds ratio [OR]: 4.5), who notified sexual partners of test results (OR: 0.03), and who had tested voluntarily (OR: 0.04). Conclusion: Based on the study results this report concludes that voluntary HIV testing and encouragement of partner notification of test results should be incorporated into China’s national testing strategy.

Microbicide acceptability and associated factors among female sex workers and male clients in Kaiyuan County, Yunnan Province, China.

Objectives:To determine microbicide acceptability and associated factors among female sex workers (FSWs) and their clients in Yunnan, China. Methods:Kaiyuan County, with high rates of HIV in FSWs, in Yunnan Province was chosen as the study site. Establishments were selected using stratified sampling, and FSWs were recruited using random sampling. Male clients of FSWs were also recruited. In-depth interviews and anonymous questionnaires were used to collect data. An acceptance rate was calculated for each individual variable, and factors associated with acceptability were assessed using multivariate analysis. Results:Four hundred FSWs and 200 male clients were recruited. Microbicides were acceptable if they prevented HIV transmission effectively and safely, were lubricating, effective up to 24 hours, and <10 China Yuan (CNY) (US