Xiang-Sheng Chen

University of California, Los Angeles, Los Angeles, California, United States

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Publications (84)479.86 Total impact

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    ABSTRACT: Introduction: 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). Methods: A baseline survey and a prospective cohort study were conducted among MSM in Yangzhou and Guangzhou from July 2009 to September 2010. A total of 622 MSM (317 from Yangzhou and 305 from Guangzhou) were screened for eligibility. Prevalence and incidence of HIV infection, as well as its risk factors, were investigated. Results: Baseline HIV prevalence was 14.5%, and overall HIV incidence density was 6.78 per 100 person-years (PY) among Yangzhou MSM. Risk factors for HIV prevalence that were significant in multivariate models were older age, married status, unprotected sex with female partners, sexually transmitted disease (STD)-associated symptoms and syphilis positivity. Risk factors for HIV incidence that were significant in multivariate models were STD-associated symptom and syphilis positivity. Compared to Yangzhou MSM, Guangzhou MSM had a lower HIV prevalence (6.2%; p<0.05) and lower overall HIV incidence density (5.77 per 100 PY). Risk factors for HIV prevalence that were significant in multivariate models were married status, unprotected anal sex with men and syphilis positivity. The single risk factor for HIV incidence that was significant in multivariate models was unprotected anal sex with men. Conclusions: This study showed a high prevalence and incidence of HIV among Yangzhou MSM, which suggest a more serious HIV epidemic than that in large-sized cities. Further investigation targeting MSM in medium-sized cites is urgently needed to prevent the spread of the HIV epidemic in China.
    Journal of the International AIDS Society 08/2014; 17(1):18849. · 4.21 Impact Factor
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    ABSTRACT: Genital warts (GW) are the most common sexually transmitted infections. To date, few studies using a human papillomavirus (HPV)-specific questionnaire have focused on the impact of quality of life (QoL) among patients with GW in developing countries. The origins of GW related psychosocial burdens and variations between genders were poorly characterized as well.
    BMC Public Health 07/2014; 14(1):739. · 2.32 Impact Factor
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    ABSTRACT: Antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a major problem worldwide. This study investigated the AMR, genetic ceftriaxone resistance determinants and molecular epidemiology of N. gonorrhoeae in Nanjing, China.
    Journal of Antimicrobial Chemotherapy 07/2014; · 5.34 Impact Factor
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    ABSTRACT: 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. 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. 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%). 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).
    PLoS ONE 05/2014; 9(5):e96364. · 3.53 Impact Factor
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    ABSTRACT: To estimate the prevalence of HIV and syphilis, incidence of syphilis and to identify the correlates of syphilis infection among heterosexual male attendees of sexually transmitted infection (STI) clinics (MSC). A cohort study of one-year duration was conducted in Yangzhou and Changzhou cities in Jiangsu province of China. The baseline survey commenced in June 2009, recruited 1225 consenting adult MSCs (609 in Yangzhou and 617 in Changzhou) through STI-clinic based convenience sampling. Baseline HIV and syphilis prevalence were 0.49% and 17.29% respectively. Syphilis incidence rate was 7.22 per 100 person-years (6.53 in Yangzhou and 7.76 in Changzhou) during the 6-month follow-up with retention fractions of 27.38% and 35.15% for Yangzhou and Changzhou respectively. Majority of the participants were middle-aged, high school educated, married, living with partners and non-migrants. Very few subjects reported recent and consistent condom-use with regular partners. Although considerable number of MSCs reported recent sexual exposure with female sex workers (FSW) and non-FSW casual partners, the proportion of reported condom use was very low during those exposures. In multivariate analyses higher age, having recent sex with FSWs and being HIV-positive were associated with higher syphilis sero-positivity while higher education was protective. In bivariate analyses, being married, divorced/widowed, official residency of the study cities and non-use of condom with regular partners predicted higher risk. Considering the potential bridging role of MSCs between high and low-risk populations, effective intervention strategies among them targeting the correlates of syphilis infection are urgently called for in Jiangsu province of China.
    PLoS ONE 04/2014; 9(4):e95289. · 3.53 Impact Factor
    This article is viewable in ResearchGate's enriched format
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    ABSTRACT: Background. Epidemic of HIV and syphilis among MSM are major public health concerns in most parts of China. Dearth of information regarding the current trend of HIV in this hard-to-reach population in several regions including Jiangsu coupled with the re-emergence of syphilis called for an effort to understand the dynamics of the dual epidemic in this province. Methods. To estimate the occurrence and burden of these two sexually transmitted diseases and the distribution of their potential socio-behavioral correlates among MSM in Jiangsu, two cohort studies were conducted in Yangzhou and Changzhou cities. Results. Among total 839 participants, 48% were married, 51.7% had sex with women in last 6 months and 25.5% did not use condom during their last anal intercourse. The observed incidence of HIV was 13.59 & 12.62 and syphilis was 7.33 & 13.25 per 100 person-years among the participants of n Yangzhou and Changzhou respectively. The baseline prevalence of HIV and Syphilis were 16.0% and 29.9% in Yangzhou and 13.6% and 14.9% in Changzhou respectively. Conclusion. Considerably high incidence and prevalence of HIV and syphilis among participants and their potential bridging role in transmitting these infections to general population in Yangzhou and Changzhou cities thus called for urgent effective intervention strategies.
    Clinical Infectious Diseases 03/2014; · 9.42 Impact Factor
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    ABSTRACT: To evaluate the performance of the Abbott RealTime CT/NG assay for detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) among female sex workers (FSWs) in China. Cervical swabs from 997 participants were blindly detected by the Abbott RealTime CT/NG assay on the automated m2000 molecular platform and Roche Cobas Amplicor CT/NG assay. Discrepant analysis were confirmed by the Qiagen care CT PCR assay. The sample was defined as candidate nvCT-positive if it was CT positive in the Abbott m2000 assay, but CT negative in the other two assays. 25 specimens that were discordant for CT and 26 specimens that were discordant for NG between the two assays were resolved by Qiagen care CT & NG PCR assays. The sensitivity and specificity, respectively, for Abbott m2000 assay were 92.59% and 100% for CT and 95.45% and 99.90% for NG. The positive predictive value (PPV) and negative predictive value (NPV) of Abbott m2000 assay were100% and 98.52% for CT and 95.5% and 99.90% for NG, respectively. No candidate new-variant CT(nvCT)specimens were identified. Abbott RealTime CT/NG assay were more specify for CT and NG detection, however, its sensitivity for CT and NG were a little bit lower than Roche Cobas Amplicor CT/NG assay. Abbott RealTime CT/NG assay had higher PPV for NG detection than Roche Cobas Amplicor CT/NG assay; it would be more suitable for screening for population with low-prevalence NG. There is currently no evidence that nvCT is present in FSWs in China.
    PLoS ONE 03/2014; 9(3):e89658. · 3.53 Impact Factor
    This article is viewable in ResearchGate's enriched format
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    ABSTRACT: Although Mycoplasma genitalium (MG) is a common sexually transmitted infection (STI), very little information regarding the prevalence of MG among MSM (men who have sex with men) is available in China. The objective of this study was to determine the prevalence of MG among MSM in the city of Shenzhen, Guangdong Province, China, and to identify the potential risk factors associated with MG infection in this population. Between January and May 2010, a total of 409 MSM were recruited in Shenzhen, Guangdong Province, China. An anonymous questionnaire was used to collect information regarding their sociological and sexual behaviors. In addition, their first-void urine (FVU) samples and rectal swabs were collected for PCR-based MG testing. Among the 406 FVU and 405 rectal swab samples were collected from 409 MSM, the overall MG prevalence was 8.1% (33/406, 95% CI 5.7%-10.6%), with a FVU positivity of 3.4% (95% CI 1.7%-5.4%) and a rectal positivity of 5.4% (95% CI 3.5%-7.7%). Using both univariate and multivariable logistic regression analyses, urethral MG infection was significantly associated with having more heterosexual behaviors (AOR 7.16, 95% CI 1.89-27.13,) and with having unprotected anal intercourse in the past six months (AOR 4.80, 95%CI 1.40-16.47). Rectal MG infection was significantly associated with HIV infection based on univariate logistic regression analysis (OR = 4.49, 95% CI 1.18-17.12). In this study, we investigated the prevalence of MG infection in the population of interest, as determined from both urethral and rectal specimen. We showed that MG was more prevalent in MSM who had bisexual behaviors compared to those who engaged only in homosexual behaviors. Further work is needed to establish the mode of MG transmission and to identify its role in HIV transmission. Meanwhile, more attention should be paid to MG infection among MSMs, and especially bisexual MSMs, which might have critical implications for effective HIV/STD control in China.
    BMC Public Health 02/2014; 14(1):195. · 2.32 Impact Factor
    This article is viewable in ResearchGate's enriched format
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    ABSTRACT: Despite widespread biomedical advances in treatment and prevention, HIV and other sexually transmitted infections (STI) continue to affect a large portion of the world's population. The profoundly social nature of behaviorally driven epidemics and disparities across socioeconomic divides in the distribution of HIV/STI and care outcomes emphasize the need for innovative, multilevel interventions. Interdisciplinary approaches to HIV/STI control are needed to combine insights from the social and biological sciences and public health fields. In this concluding essay to a Special Issue on HIV/STI in south China, we describe the evolution of the region's HIV/STI epidemics and the government response, then synthesize findings from the 11 studies presented in this issue to extend seven recommendations for future HIV/STI prevention and care research in China. We discuss lessons learned from forging international collaborations between the social and biological sciences and public health to inform a shared research agenda to better meet the needs of those most affected by HIV and other STI.
    AIDS and Behavior 01/2014; · 3.49 Impact Factor
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    ABSTRACT: To estimate the prevalence of sexually transmitted infections (STIs) among female sex workers (FSWs) in the Jiangsu Province, China and measure the association of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections with their potential correlates. A cross-sectional study on a representative sample of FSWs in Yangzhou and Changzhou cities of Jiangsu was conducted. 185 sex-work venues in Yangzhou and 174 in Changzhou were selected by stratified random sampling. 2972 FSWs (1108 in Yangzhou and 1864 in Changzhou), aged 15 years or more, who agreed to participate and provided blood sample for HIV and syphilis testing were interviewed in these venues. Cervical specimens from 849 randomly chosen participants were then tested for CT and NG. Proportions of young, school-educated, currently married FSWs who were living alone, migrated from other provinces and engaged in unprotected vaginal intercourse in past 3 months (UVI) were relatively high. Prevalence of HIV, syphilis, CT and NG were 0.20%, 4.88%, 14.61% and 5.42% respectively. Younger age, living alone or with persons other than partners/family members, engaging in UVI and having other STIs seemed to be associated with higher risk of CT or NG infection. Being divorced/widowed and working in middle/low-level venues were identified as additional risk factors for NG. Based on a representative sample, this initial effort to identify the correlates of CT/NG infections among FSWs of Jiangsu revealed that focused interventions targeting high-risk FSWs are urgently required for controlling STI epidemics in Yangzhou and Changzhou where substantial number of STI cases were identified.
    PLoS ONE 01/2014; 9(1):e85985. · 3.53 Impact Factor
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    ABSTRACT: The objective of this study was to determine the prevalence of urethral Mycoplasma genitalium infections among male patients attending a sexually transmitted disease (STD) clinic in China and identify risk factors associated with this disease. A total of 423 patients were recruited in Hezhou City, Guangxi Province, China, and each was requested to complete a questionnaire regarding sociological and sexual behaviors. First-void urine samples were collected for M. genitalium analysis by polymerase chain reaction. Of the 406 urine samples collected, 114 were M. genitalium-positive, giving a prevalence rate of 28.1%. Univariate logistic regression analysis showed that M. genitalium infection was associated with younger age, having received at least senior high school education, and single marital status. In both univariate and multivariate logistic regression analyses, M. genitalium infection was found to be associated with lack of symptoms for STD in the past year (adjusted odds ratio [AOR] = 2.839; 95% CI = 1.495-5.392; P = 0.001), no use of condoms with steady partners in the past year (AOR = 2.830; 95% CI = 1.468-5.455; P = 0.002), and having sexual encounters with female sexual workers within the past 3 months (AOR = 2.955; 95% CI = 1.637-5.336; P < 0.0003). The observed high rate of M. genitalium infection among male STD patients in Hezhou City indicates an M. genitalium epidemic in the study population; thus, the national surveillance program and clinical health providers in China should more closely monitor this disease.
    Japanese journal of infectious diseases. 01/2014; 67(1):17-21.
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    ABSTRACT: Brief non-commercial sexual encounters among patrons of social venues are increasing in China, but whether these encounters increase syphilis risk is unknown. We surveyed and tested 797 men and women at randomly selected social venues in urban Liuzhou and three surrounding counties. The percent reporting recent non-commercial one-time sex ranged from 14.5 % of county women to 24.8 % of urban men. 2.4 % of men and 3.7 % of women had a positive rapid syphilis test. Men reporting non-commercial one-time sex were significantly more likely to have a positive rapid syphilis test than other men (7.4 vs. 0.9 %). Among women, commercial sex was more strongly associated with syphilis than non-commercial one-time sex (6.0 vs. 0.7 %). Recent one-time sex was common and associated with syphilis among men. Venue-based HIV/STI prevention methods may be warranted among persons who do not engage in commercial sex, but frequently engage in one-time sex.
    AIDS and Behavior 11/2013; 18(S2). · 3.49 Impact Factor
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    ABSTRACT: This study aimed to investigate the prevalence of penicillinase-producing Neisseria gonorrhoeae (PPNG) and their blaTEM-135 gene variant in 2007 and 2012 in Nanjing, China. In addition, molecular epidemiological typing of all isolates was performed to elucidate the genetic relationships of the PPNG strains. A total of 199 and 77 N. gonorrhoeae isolates were collected at the National Center for STD Control in 2007 and 2012, respectively. Nitrocefin tests were performed to identify PPNG. Mismatch amplification mutation assay was used to identify blaTEM-135. All isolates were genotyped using N. gonorrhoeae multiantigen sequence typing (NG-MAST), and additionally, porB-based phylogenetic analysis was performed for the PPNG isolates. The total prevalence of PPNG isolates was 41% (114/276) and 58% (66/114) of these PPNG isolates possessed blaTEM-135. In 2007, 45% (90/199) produced β-lactamase, and of those PPNG, 58% (52/90) possessed blaTEM-135. In 2012, 31% (24/77) were PPNG, and 58% (14/24) of those isolates contained blaTEM-135. There were 162 NG-MAST STs among the 276 isolates, and 89 of those were novel STs. A strong association between specific NG-MAST STs and blaTEM-135 was found, and the porB-based phylogenetic analysis showed a distant evolutionary relationship between isolates in 2007 and isolates in 2012. A high prevalence of PPNG and blaTEM-135 was found in Nanjing, China. blaTEM-135 might be a precursor in the evolution into an extended-spectrum β-lactamase that can degrade ceftriaxone, which stresses the need to continuously monitor PPNG, blaTEM-135, and additional evolving blaTEM gene variants.
    Sexually transmitted diseases 11/2013; 40(11):872-876. · 2.58 Impact Factor
  • Xiang-Sheng Chen
    The Lancet Infectious Diseases 11/2013; 13(11):918-9. · 19.45 Impact Factor
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    ABSTRACT: To determine the prevalence and correlates of syphilis among pregnant women in rural areas of South China. Point-of-care syphilis testing was provided at 71 health facilities in less developed, rural areas of Guangdong Province. Positive samples were confirmed at a local referral center by toluidine red unheated serum tests (TRUST) and Treponema pallidum particle agglutination (TPPA) tests. Altogether 27,150 pregnant women in rural Guangdong were screened for syphilis. 106 (0.39%) syphilis cases were diagnosed, of which 78 (73.6%) received treatment for syphilis. Multivariate analysis revealed that older pregnant women (31-35 years old, aOR 2.7, 95% CI 0.99-7.32; older than 35 years old, aOR 5.9, 95% CI 2.13-16.34) and those with a history of adverse pregnant outcomes (aOR 3.64, 95% CI 2.30-5.76) were more likely to be infected with syphilis. A high prevalence of syphilis exists among pregnant women living in rural areas of South China. Enhanced integration of syphilis screening with other routine women's health services (OB GYN, family planning) may be useful for controlling China's syphilis epidemic.
    PLoS ONE 08/2013; 8(8):e72149. · 3.53 Impact Factor
  • Xiang-Sheng Chen
    The Lancet Infectious Diseases 08/2013; 13(8):651. · 19.45 Impact Factor
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    ABSTRACT: The objective of this study was to assess the distribution of Chlamydia trachomatis genovars in male sexually transmitted disease (STD) clinic patients from 1 province in eastern China (Jiangsu) and 3 provinces in southern China (Guangdong, Guangxi, and Hainan). Urine specimens (n = 140) were collected from 46 public STD clinics in the 4 provinces. Specimens that tested positive for C. trachomatis by polymerase chain reaction were genotyped for the infecting C. trachomatis strain by amplifying and sequencing the genovar-specific ompA gene, which encodes the chlamydial major outer-membrane protein. Nine C. trachomatis genovars were identified from 129 specimens; they consisted of the F (25.6%), E (17.1%), J (16.3%), D (15.5%), G (11.6%), K (5.4%), H (3.9%), I (1.6%), and B (0.8%) genovars. Nine genovars were found in specimens from Guangxi province, 6 were found in specimens from each of Guangdong and Hainan provinces, but only 5 were found in specimens from Jiangsu province. Genovar G/Ga was shown to be endemic among male patients in southern China.
    Japanese journal of infectious diseases. 07/2013; 66(1):69-71.
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    ABSTRACT: The re-emerging syphilis epidemic in China is documented among sex workers, but little is known about STI risk among the broader group of women who work at entertainment and service venues, many of whom do not self-identify as sex workers. In 2009 in Liuzhou, China, community informants identified venues where people meet sexual partners. Characteristics of a stratified random sample of venues were collected during venue visits. Female staff at 42 venues were interviewed and tested for syphilis. The results showed that venue characteristics, worker behaviors, and syphilis prevalence differed by venue type. Service venue workers had more sexual partners, were more likely to report sex work, and more likely to have a positive syphilis test than entertainment venue workers (prevalence ratio: 5.4; 95 % CI 1.4-20.6). To conclude, risk of syphilis differs by venue type and is higher at service venues, even among women who do not report commercial sex.
    AIDS and Behavior 07/2013; 18(Suppl 2). · 3.49 Impact Factor
    This article is viewable in ResearchGate's enriched format
  • Xiang-Sheng Chen, Yue-Ping Yin, Qian-Qiu Wang, Bao-Xi Wang
    Chinese medical journal 07/2013; 126(14):2774-9. · 1.02 Impact Factor
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    ABSTRACT: A cross-sectional study that investigated the association between cervical infection of Chlamydia trachomatis, Neisseria gonorrhoeae, or Mycoplasma genitalium and infection with high-risk types of human papillomavirus among female sex workers in China found that the presence of cervical C. trachomatis or M. genitalium infection was independently associated with infection with certain high-risk types of specific high-risk human papillomavirus among this population.
    Sexually transmitted diseases 06/2013; 40(6):493-5. · 2.58 Impact Factor

Publication Stats

857 Citations
479.86 Total Impact Points


  • 2014
    • University of California, Los Angeles
      • Department of Epidemiology
      Los Angeles, California, United States
  • 2012–2014
    • Chinese Center For Disease Control And Prevention
      Peping, Beijing, China
    • Partners HealthCare
      Boston, Massachusetts, United States
    • Shenzhen Center for Disease Control and Prevention
      Shen-ch’üan-shih, Zhejiang Sheng, China
    • London School of Hygiene and Tropical Medicine
      Londinium, England, United Kingdom
    • Peking Union Medical College Hospital
      Peping, Beijing, China
  • 2010–2014
    • Chinese Academy of Medical Sciences
      Peping, Beijing, China
    • Johns Hopkins Bloomberg School of Public Health
      Baltimore, Maryland, United States
    • Massachusetts General Hospital
      • Department of Medicine
      Boston, MA, United States
  • 2013
    • Guangzhou Institute of Dermatology
      Shengcheng, Guangdong, China
  • 2012–2013
    • University of North Carolina at Chapel Hill
      • Carolina Population Center
      North Carolina, United States
  • 2011–2012
    • China Academy of Chinese Medical Sciences
      Peping, Beijing, China
    • Jiangsu Provincial Center for Disease Control and Prevention
      Chiang-tu, Jiangsu Sheng, China
  • 2007
    • University of California, San Francisco
      San Francisco, California, United States
    • Qingdao University
      Tsingtao, Shandong Sheng, China