Xiang Sheng Chen

Syphilis in China: results of a national surveillance programme

n Summaryn n Backgroundn After a massive syphilis epidemic in the first half of the 20th century, China was able to eliminate this infection for 20 years (1960–80). However, substantial changes in Chinese society have been followed by a resurgent epidemic of sexually transmitted diseases. Sporadic reports have provided clues to the magnitude of the spread of syphilis, but a national surveillance effort is needed to provide data for planning and intervention.n n n Methodsn We collected and assessed case report data from Chinas national sexually transmitted disease surveillance system and sentinel site network.n n n Findingsn In 1993, the reported total rate of cases of syphilis in China was 0·2 cases per 100u2008000, whereas primary and secondary syphilis alone represented 5·7 cases per 100u2008000 persons in 2005. The rate of congenital syphilis increased greatly with an average yearly rise of 71·9%, from 0·01 cases per 100u2008000 livebirths in 1991 to 19·68 cases per 100u2008000 livebirths in 2005.n n n Interpretationn The results suggest that a range of unique biological and social forces are driving the spread of syphilis in China. A national campaign for detection and treatment of syphilis, and a credible prevention strategy, are urgently needed.n n

Syphilis and social upheaval in China.

Syphilis was nearly eliminated from China 50 years ago but is now the most commonly reported communicable disease in Shanghai. Dr. Joseph Tucker and colleagues write that the Chinese syphilis epidemic holds important lessons about social and environmental influences on sexual health.

China's syphilis epidemic : A systematic review of seroprevalence studies

Objective: The objective of this study was to investigate syphilis prevalence among low- and high-risk groups in China. Goal: The goal of this study was to explore the magnitude of China’s syphilis epidemic. Study Design: A systematic literature review of syphilis seroprevalence studies in China was performed searching PubMed and the Chinese Periodicals Database (CPD). Results: Five and 169 studies were retrieved from PubMed and the CPD, respectively. From 2000 to 2005, select low-risk groups had the following median syphilis prevalence: antenatal women (0.45%), premarital individuals (0.66%), and food and service employees (0.3%). Select high-risk groups had the following median prevalence: incarcerated female sex workers (12.49%), drug users (6.81%), and men who have sex with men (14.56%). In the last decade, prevalence has increased in all groups with the steepest rises seen among high-risk groups. Conclusions: Syphilis infection is increasing among low- and high-risk groups in China, suggesting unsafe sexual behavior that may accelerate HIV transmission and challenge current syphilis prevention and control efforts.

Detection of acute and established HIV infections in sexually transmitted disease clinics in Guangxi, China: Implications for screening and prevention of HIV infection

BACKGROUNDnHuman immunodeficiency virus (HIV) has spread throughout China and to some degree has penetrated the general heterosexual population in some regions.nnnMETHODSnA cross-sectional survey of 11,461 sexually transmitted disease (STD) clinic attendees in 8 cities in Guangxi, China, was conducted for syphilis and for acute and established HIV infections.nnnRESULTSnThe prevalence of acute and established HIV infections was 1.2% among the participants. Five acute (preseroconversion) HIV infections were detected. Multivariate analysis showed that HIV infection was independently related to unmarried status (odds ratio [OR], 1.73 [95% confidence interval {CI}, 1.00-2.99), less education (OR for less than primary school, 4.21 [90% CI, 1.21-14.58]), residence in city A (OR, 11.48 [95% CI, 2.05-64.31]) or city B (OR, 7.93 [95% CI, 1.75-35.91]), working in the entertainment industry (OR, 3.98 [95% CI, 1.14-13.88]), injection drug use (OR, 25.09 [95% CI, 10.43-60.39]), no condom use during most recent sexual intercourse (OR, 4.97 [95% CI, 1.38-17.88]), and syphilitic infection (OR, 1.91 [95% CI, 1.03-3.56]).nnnCONCLUSIONSnHIV prevalence in STD clinics is significantly greater than that in the general population, and subjects were identified who would be missed by conventional surveillance. Chinas nationwide system of public STD clinics, which reach down to the township level, should be used for HIV control programs.

A comparison of respondent-driven and venue-based sampling of female sex workers in Liuzhou, China

Objectives To compare two methods for sampling female sex workers (FSWs) for bio-behavioural surveillance. We compared the populations of sex workers recruited by the venue-based Priorities for Local AIDS Control Efforts (PLACE) method and a concurrently implemented network-based sampling method, respondent-driven sampling (RDS), in Liuzhou, China. Methods For the PLACE protocol, all female workers at a stratified random sample of venues identified as places where people meet new sexual partners were interviewed and tested for syphilis. Female workers who reported sex work in the past 4u2005weeks were categorised as FSWs. RDS used peer recruitment and chain referral to obtain a sample of FSWs. Data were collected between October 2009 and January 2010. We compared the socio-demographic characteristics and the percentage with a positive syphilis test of FSWs recruited by PLACE and RDS. Results The prevalence of a positive syphilis test was 24% among FSWs recruited by PLACE and 8.5% among those recruited by RDS and tested (prevalence ratio 3.3; 95% CI 1.5 to 7.2). Socio-demographic characteristics (age, residence and monthly income) also varied by sampling method. PLACE recruited fewer FSWs than RDS (161 vs 583), was more labour-intensive and had difficulty gaining access to some venues. RDS was more likely to recruit from areas near the RDS office and from large low prevalence entertainment venues. Conclusions Surveillance protocols using different sampling methods can obtain different estimates of prevalence and population characteristics. Venue-based and network-based methods each have strengths and limitations reflecting differences in design and assumptions. We recommend that more research be conducted on measuring bias in bio-behavioural surveillance.

An expanding syphilis epidemic in China: epidemiology, behavioural risk and control strategies with a focus on low-tier female sex workers and men who have sex with men

Syphilis has made a dramatic resurgence in China during the past two decades. During the Cultural Revolution (1966–76), sexually transmitted infections (STI) were so uncommon that they were removed from standard Chinese medical training curricula.1 As Chinas market economy expanded during 1980s economic reforms, reported STI, including syphilis infection, quickly re-appeared. An evolving STI reporting infrastructure largely assembled in the 1990s has noted increasing syphilis cases, particularly during the past 5u2005years (figure 1).2 3 Now syphilis is among the top five reported communicable diseases in many major province-level municipalities and provinces.4 While Chinas syphilis case reporting system and potential determinants of spread have been outlined in other reviews,2 there have been many studies on syphilis infection among female sex workers (FSW),5 6 this review analyses syphilis in China from the perspective of two critical high-risk populations: men who have sex with men (MSM) and low-tier FSW. Here we define low-tier FSW as women who usually solicit clients on the street or public outdoor places and sell sex for less than approximately €2–10 per client. Although preventing adverse outcomes associated with syphilis in pregnancy is important,7 this review focuses …

Systematic differences in risk behaviors and syphilis prevalence across types of female sex workers: a preliminary study in Liuzhou, China.

Background: Female sex workers (FSWs) have become one of the key populations for HIV/STI control in China. Categorization of FSWs can help prioritize HIV/STI intervention efforts. We examined 2 possible categorizations of FSWs and the relationship with syphilis infection risk in Liuzhou City, China. Methods: From October 2009 to February 2010, a total of 583 FSWs recruited by respondent-driven sampling in a cross-sectional survey were tested for syphilis and interviewed to collect sociodemographic and behavioral information. Respondents were categorized based on transaction price for vaginal sex and type of sex work location. The relationship between the 2 categorizations and syphilis infection risk was assessed using univariate and multivariate logistic regression analysis. Results: The prevalence rates of lifetime and active syphilis infection were 8.6% and 4.1%, respectively. Lifetime and active syphilis prevalence was higher among FSWs in the lowest price category (52.7% and 25.4%, respectively) and those working in streets (69.7% and 39.8%, respectively) or through telephone (46.3% and 17.0%, respectively). Multivariate analysis showed that lifetime syphilis prevalence was significantly higher among street- (adjusted odds ratio [AOR]: 38.7, 95% confidence intervals [CI]: 10.7–139.9) and telephone-based FSWs (AOR: 10.8, 95% CI: 3.3–35.1), and that active syphilis prevalence was significantly higher among street-based FSWs (AOR: 15.2, 95% CI: 3.7–62.1) after adjusting for demographic and behavioral factors. Conclusions: Categorization based on sex work location was more closely related to the risk of syphilis infection than the price classification. Street- and telephone-based FSWs had significantly higher risk of syphilis infection. Focused interventions among these particular high-risk FSWs subgroups are warranted.

Molecular Typing of Treponema pallidum: A Systematic Review and Meta-Analysis

Background Syphilis is resurgent in many regions of the world. Molecular typing is a robust tool for investigating strain diversity and epidemiology. This study aimed to review original research on molecular typing of Treponema pallidum (T. pallidum) with three objectives: (1) to determine specimen types most suitable for molecular typing; (2) to determine T. pallidum subtype distribution across geographic areas; and (3) to summarize available information on subtypes associated with neurosyphilis and macrolide resistance. Methodology/Principal Findings Two researchers independently searched five databases from 1998 through 2010, assessed for eligibility and study quality, and extracted data. Search terms included “Treponema pallidum,” or “syphilis,” combined with the subject headings “molecular,” “subtyping,” “typing,” “genotype,” and “epidemiology.” Sixteen eligible studies were included. Publication bias was not statistically significant by the Begg rank correlation test. Medians, inter-quartile ranges, and 95% confidence intervals were determined for DNA extraction and full typing efficiency. A random-effects model was used to perform subgroup analyses to reduce obvious between-study heterogeneity. Primary and secondary lesions and ear lobe blood specimens had an average higher yield of T. pallidum DNA (83.0% vs. 28.2%, χ2u200a=u200a247.6, p<0.001) and an average higher efficiency of full molecular typing (80.9% vs. 43.1%, χ2u200a=u200a102.3, p<0.001) compared to plasma, whole blood, and cerebrospinal fluid. A pooled analysis of subtype distribution based on country location showed that 14d was the most common subtype, and subtype distribution varied across geographic areas. Subtype data associated with macrolide resistance and neurosyphilis were limited. Conclusions/Significance Primary lesion was a better specimen for obtaining T. pallidum DNA than blood. There was wide geographic variation in T. pallidum subtypes. More research is needed on the relationship between clinical presentation and subtype, and further validation of ear lobe blood for obtaining T. pallidum DNA would be useful for future molecular studies of syphilis.

Scaling up syphilis testing in China: implementation beyond the clinic

China is experiencing a syphilis epidemic of enormous proportions. The regions most heavily affected by syphilis correspond to regions where sexually transmitted HIV infection is also a major public health threat. Many high-risk patients in China fail to receive routine syphilis screening. This missed public health opportunity stems from both a failure of many high-risk individuals to seek clinical care and a disconnect between policy and practice. New point-of-care syphilis testing enables screening in non-traditional settings such as community organizations or sex venues. This paper describes the current Chinese syphilis policies, suggests a spatiotemporal framework (based on targeting high-risk times and places) to improve screening and care practices, and emphasizes a syphilis control policy extending beyond the clinical setting.

Primary syphilis cases in Guangdong Province 1995-2008: Opportunities for linking syphilis control and regional development

BackgroundSyphilis cases have risen in many parts of China, with developed regions reporting the greatest share of cases. Since syphilis increases in these areas are likely driven by both increased screening and changes in sexual behaviours, distinguishing between these two factors is important. Examining municipal-level primary syphilis cases with spatial analysis allows a more direct understanding of changing sexual behaviours at a more policy-relevant level.MethodsIn this study we examined all reported primary syphilis cases from Guangdong Province, a southern province in China, since the disease was first incorporated into the mandatory reporting system in 1995. Spatial autocorrelation statistics were used to correlate municipal-level clustering of reported primary syphilis cases and gross domestic product (GDP).ResultsA total of 52,036 primary syphilis cases were reported over the period 1995-2008, and the primary syphilis cases increased from 0.88 per 100,000 population in 1995 to 7.61 per 100,000 in 2008. The Pearl River Delta region has a disproportionate share (44.7%) of syphilis cases compared to other regions. Syphilis cases were spatially clustered (p = 0.01) and Morans I analysis found that syphilis cases were clustered in municipalities with higher GDP (p = 0.004).ConclusionsPrimary syphilis cases continue to increase in Guangdong Province, especially in the Pearl River Delta region. Considering the economic impact of syphilis and its tendency to spatially cluster, expanded syphilis testing in specific municipalities and further investigating the costs and benefits of syphilis screening are critical next steps.