Baoxi Wang

Prevalence of syphilis infection in different tiers of female sex workers in China: implications for surveillance and interventions

BackgroundSyphilis has made a dramatic resurgence in China during the past two decades and become the third most prevalent notifiable infectious disease in China. Female sex workers (FSWs) have become one of key populations for the epidemic. In order to investigate syphilis infection among different tiers of FSWs, a cross-sectional study was conducted in 8 sites in China.MethodsSerum specimens (n = 7,118) were collected to test for syphilis and questionnaire interviews were conducted to obtain socio-demographic and behavioral information among FSWs recruited from different types of venues. FSWs were categorized into three tiers (high-, middle- and low-tier FSWs) based on the venues where they solicited clients. Serum specimens were screened with enzyme-linked immunosorbent assay (ELISA) for treponemal antibody followed by confirmation with non-treponemal toluidine red unheated serum test (TRUST) for positive ELISA specimens to determine syphilis infection. A logistic regression model was used to determine factors associated with syphilis infection.ResultsOverall syphilis prevalence was 5.0% (95%CI, 4.5-5.5%). Low-tier FSWs had the highest prevalence (9.7%; 95%CI, 8.3-11.1%), followed by middle-tier (4.3%; 95%CI, 3.6-5.0%, P < 0.001) and high-tier FSWs (2.2%; 95%CI, 1.6-2.9%, P < 0.001). Factors independently associated with syphilis infection included older age, lower education level, geographic location, lower tier of typology, and injection drug use.ConclusionsThis multi-site survey showed a high prevalence of syphilis infection among FSWs and substantial disparities in syphilis prevalence by the tier of FSWs. The difference in syphilis prevalence is substantial between different tiers of FSWs, with the highest rate among low-tier FSWs. Thus, current surveillance and intervention activities, which have low coverage in low-tier FSWs in China, should be further examined.

HIV prevalence varies between female sex workers from different types of venues in southern China.

We conducted a cross-sectional study on prevalence of human immunodeficiency virus (HIV) and syphilis among female sex workers (FSWs) recruited from different types of venues in 6 cities in China. Among 5322 FSWs (1379 were from high-tier venues, 2482 from middle-tier venues, and 1461 from low-tier venues, respectively), overall HIV prevalence was 0.54% (95% confidence interval [CI], 0.37%- 0.76%). By typology of venues where FSWs solicited clients, the prevalence was 1.37% (95% CI, 0.89%-2.11%) in low-tier venues, 0.28% (95% CI, 0.14%- 0.58%) in middle-tier venues, and 0.07% (95% CI, 0.01%-0.41%) in high-tier venues. The final logistic regression model showed an association of having had HIV infection with working in low-tier venues (adjusted odds ratio 2.73; 95% CI, 1.12-6.67) and coming from Guangxi Province (adjusted odds ratio, 7.89; 95% CI, 1.65-37.64). It can be concluded that FSWs working in low-tier venues (on the streets or public outdoor places) had higher risk of HIV infection than other venues. Such subgroup of FSWs should be efficiently covered by the current HIV/STD surveillance and intervention programs in China.

The prevalences of Neisseria gonorrhoeae and Chlamydia trachomatis infections among female sex workers in China.

BackgroundSexually transmitted infections (STIs) have become a major public health problem among female sex workers (FSWs) in China. There have been many studies on prevalences of HIV and syphilis but the data about Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) infections are limited in this population in China.MethodsA cross-sectional study was performed among FSWs recruited from different types of venues in 8 cities in China. An interview with questionnaire was conducted, followed by collection of a blood and cervical swab specimens for tests of HIV, syphilis, NG and CT infections.ResultsA total of 3,099 FSWs were included in the study. The overall prevalence rates of HIV, syphilis, NG and CT were 0.26%, 6.45%, 5.91% and 17.30%, respectively. Being a FSW from low-tier venue (adjusted odds ratios [AOR]=1.39) had higher risk and being age of ≥ 21 years (AOR=0.60 for 21–25 years; AOR=0.29 for 26–30 years; AOR=0.35 for 31 years or above) had lower risk for CT infection; and having CT infection was significantly associated with NG infection.ConclusionsThe high STI prevalence rates found among FSWs, especially among FSWs in low-tier sex work venues, suggest that the comprehensive prevention and control programs including not only behavioral interventions but also screening and medical care are needed to meet the needs of this population.

HPV Infections among MSM in Shenzhen, China

Background An increasing incidence of anal cancer among men, especially men who have sex with men (MSM) suggests a need to better understand anal human papillomavirus (HPV) infection among this group. Methods A cross-sectional study was conducted among MSM in Shenzhen, China. Blood was collected for HIV serological testing and syphilis serological screening, and anal swabs were collected for HPV genotyping. Difference of HPV prevalence between HIV seropositive and HIV seronegative MSM was assessed by chi-square test. Factors associated with anal canal HPV infection were assessed by univariate and multivariate logistic regression. Results A total of 408 MSM were recruited. HIV and HPV prevalence were 6.9% and 36.4%, respectively. HPV was detected in the anal canal in 71.4% of the HIV-positive MSM and in 33.8% of the HIV-negative MSM (P<0.001). Oncogenic types were seen more often in anal specimens of HIV-positive MSM than in specimens of HIV-negative MSM (P = 0.001). The HPV genotypes detected most frequently were HPV06 (8.2%), HPV16 (7.2%), HPV11 (6.4%), HPV18 (4.7%), HPV58 (4.7%), and HPV52 (4.2%). Conclusions In this study, HIV positive MSM had a higher burden of HPV infection, especially oncogenic HPV infection. HPV types 52 and 58 were as popular as those types designed for the currently available vaccine (HPV6, 11, 16, 18).

HIV prevalence, incidence and risk behaviours among men who have sex with men in Yangzhou and Guangzhou, China: a cohort study

In China, the prevalence and incidence of HIV among men who have sex with men (MSM) in large‐sized cities have drawn much attention. In contrast, there has been a paucity of research focussing on the sexual health of MSM of medium‐sized cities. This study fills this important gap in the knowledge by investigating the sexual health of MSM in a medium‐sized city (Yangzhou) and a large‐sized city (Guangzhou).

HIV/STD pattern and its associated risk factors among male STD clinic attendees in China: a foci for HIV intervention

BackgroundPrevious studies suggested a high prevalence of STDs including HIV among female sex workers and men who have sex with men in China, but little was known about the prevalence in male patients attending public STD clinics. The aim of this study was to investigate STD patterns and HIV prevalence among male STD clinic attendees in different areas in China and the associated risk factors. The feasibility of Provider-initiated HIV testing and counseling (PITC) was evaluated as well.MethodsA cross-sectional study was conducted at 46 public STD clinics in 4 provinces in China. Between July 2009 and September 2009, a total of 3243 eligible subjects were invited to participate in an interview with a structured-questionnaire for collecting socio-demographic characteristics and sexual behavioral information. They also were asked to provide venous blood samples for serological determinations of HIV and syphilis infection, and first void urine specimens for detecting Chlamydia trachomatis and Neisseria gonorrhoeae infections,ResultsOut of the 3243 eligible patients, 2951(91%) men agreed to take part in the HIV and syphilis testing. The overall prevalence rate of HIV infection was 0.7% while the rates of syphilis, N. gonorrhoeae, C. trachomatis infections were 10.7%, 4.3% and 6.9%, respectively, with the highest syphilis and N. gonorrhoeae rates in Jiangsu Province. Patients from Guangxi province, homosexual/bisexual practices and intravenous drug use were significantly associated with HIV infection in multivariate logistic regression analyses. Provider-initiated HIV testing and counseling (PITC) was well accepted by attendees, with 91% of eligible attendees agreeing to undergo HIV testing and counseling. All HIV positive patients were properly managed accordingly.ConclusionsA modest prevalence of HIV infection and substantial prevalence of other STD infections were found among male patients attending public STD clinics in China. The findings further support the introduction of HIV and syphilis PITC strategy into this important setting.

Prevalence and risk factors of HSV-2 infection and HSV-2/HIV coinfection in men who have sex with men in China: a multisite cross-sectional study.

Objectives: To determine the prevalence and risk factors of herpes simplex virus type 2 (HSV-2) infection and its coinfection with human immunodeficiency virus (HIV) in men who have sex with men (MSM) in China. Methods: A convenience sample of 1462 MSM were recruited from different settings (an STD clinic, a health center, and MSM venues) in 3 cities in China. Blood specimens were collected for testing for antibodies to HSV-2 and HIV to determinate the seroprevalence of HSV-2 infection and HSV-2/HIV coinfection. Information on sociodemographic and behavioral characteristics was collected to determine the risk factors associated with the infections. Results: The prevalence of HSV-2 infection in 1462 MSM was 16.0% (95% confidence interval [CI], 14.2%–18.0%), the prevalence of HIV infection in this population was 9.5% (95% CI, 8.1%–11.1%), and the rate of coinfection of HSV-2 and HIV was 3.2% (95% CI, 2.4%–4.3%). Multivariate logistic regression analysis showed that risk factors for HSV-2 infection included age older than 30 years, education level lower than senior high school, involvement in commercial sex work, and HIV-positive status. Education level lower than junior high school and history of sexual abuse were associated with HSV-2/HIV coinfection. Conclusions: The high prevalence of HSV-2 infection and HSV-2/HIV coinfection among MSM in China suggests that an increased focus on HSV control is warranted within Chinas prevention and intervention programs targeted toward MSM.

Prevalence and genotype distribution of human papillomavirus infection among female sex workers in Guangxi, China: Implications for interventions†

Human papillomavirus (HPV) infection is a major public health concern in women, but information on HPV among female sex workers in China is limited. The aim of the study was to estimate the prevalence and genotype distribution of HPV infection among female sex workers in two cities in Guangxi, China. A total of 811 female sex workers were recruited from venues between July and September of 2009. Data on socio‐demographic and behavior characteristics were collected, and cervical swabs were collected to determine HPV infection and genotype distribution. The overall prevalence of infection with any HPV type was 38.9%. HPV type 52 was the most prevalent type with prevalence of 11%, followed by HPV types 16, 58, 53, and CP8304, with prevalences of 6.5%, 5.7%, 5.6%, and 4.8%, respectively. HPV 16 or 18 accounted for 23.2% of all HPV positive cases. Age group <20 years was significantly associated with infection of the high‐risk and multiple types of HPV infection. A higher prevalence of multiple HPV infection was observed among female sex workers from the outdoor venues (14.0%; 95%CI, 10.6%–17.3%). These findings have important implications for developing HPV prevention programs including HPV vaccination in female sex workers. J. Med. Virol. 84:798–803, 2012.

The Effect of a Structural Intervention for Syphilis Control Among 3597 Female Sex Workers: A Demonstration Study in South China

BACKGROUND Syphilis has made a rapid resurgence in China, especially among high-risk groups including female sex workers (FSWs). METHODS Two cities in each of 3 provinces in South China were chosen and allocated to intervention or control arms. The intervention consisted of enhancing community-based syphilis screening outreach intervention with comprehensive sexually transmitted infection services at designated clinics while the control maintained routine intervention activities. Generalized linear modeling was used to examine effect of the intervention on incident syphilis infection. RESULTS A total of 8275 women were eligible, and 3597 women enrolled (n = 2011 in control arm, n = 1586 in intervention arm) in the study. The median follow-up duration was 375 days (interquartile range, 267–475). Syphilis incidence density in the intervention group was reduced by 70% (95% confidence interval, 53%–81%) compared with the incidence in the control arm. The syphilis prevention intervention benefits were robust among FSWs at low-tier venues, individuals with less than high school education, migrants, and women who did not report condom use during the last episode of sex. CONCLUSIONS Integrated sexually transmitted infection and human immunodeficiency virus prevention strategies substantially reduce syphilis incidence among FSWs, especially among those at low-tier venues. This intervention suggests the need for scaling up comprehensive FSW programs in China.

Multidrug-Resistant Neisseria gonorrhoeae Isolates from Nanjing, China, Are Sensitive to Killing by a Novel DNA Gyrase Inhibitor, ETX0914 (AZD0914)

ABSTRACT We tested the activity of ETX0914 against 187 Neisseria gonorrhoeae isolates from men with urethritis in Nanjing, China, in 2013. The MIC50, MIC90, and MIC range for ETX0914 were 0.03 μg/ml, 0.06 μg/ml, and ≤0.002 to 0.125 μg/ml, respectively. All isolates were resistant to ciprofloxacin, and 36.9% (69/187) were resistant to azithromycin. Of the isolates, 46.5% were penicillinase-producing N. gonorrhoeae (PPNG), 36% were tetracycline-resistant N. gonorrhoeae (TRNG), and 13% (24 isolates) had an MIC of 0.125 μg/ml for ceftriaxone. ETX0914 may be an effective treatment option for gonorrhea.