High chlamydia infection and its associated factors among patients seeking clinic-based STI services in Southern China: A preliminary cross-sectional study.

Objective: Chlamydia trachomatis (CT) infection is one of the most common sexually transmitted infections (STIs) worldwide. This study aimed to provide prevalence and associated factors data among patients seeking clinic-based STI services for estimating the disease burden of CT. Study design and method: A cross-sectional survey was conducted among patients attending clinics for STI services. Patients' social-demographic and behavioral information was collected and CT infection was determined by nucleic acid amplification test (NAAT) with self-collected urine specimens. Associated factors were identified using logistic regression. Results: Among the 8,324 participants, the overall prevalence was 9.0% with 10.7% for males and 8.3% for females respectively. Multivariate analysis showed that aged < 24 [adjusted odds ratio (aOR) = 1.27, 95% confidence interval (CI) = 1.01-1.59], being unmarried (aOR = 1.64, 95%CI = 1.35-2.00), having junior high school or below education level (aOR = 1.47, 95%CI = 1.13-1.91), having no access to health insurance (aOR = 1.27, 95%CI = 1.07-1.51), and being positive for Neisseria gonorrhoeae (NG, aOR = 4.49, 95%CI = 3.25-6.21) were significantly associated with CT infection. Conclusion: We found that CT infection is prevalent among patients seeking clinic-based STI services in Southern China. Targeted interventions could be implemented for patients with a higher risk of CT infection including those aged < 24, being unmarried, having junior high school or below education level, having no access to health insurance, and being positive for NG. In addition, routine CT screening could be considered a public health strategy by the government.

Associated factors of willingness to undergo routine chlamydia trachomatis screening among hospital-based patients in Shenzhen, China: a cross-sectional study.

BACKGROUND: Chlamydia trachomatis (CT) is a common sexually transmitted infection (STI) with significant morbidity. The study aimed to explore the willingness to undergo routine CT screening and its associated factors among hospital-based patients in Shenzhen. METHODS: We used data from the Shenzhen Gonorrhea and Chlamydia Intervention Programme. Participants were recruited with a stratified purposeful sampling design from 1 April 2018 to 16 May 2018. A structured questionnaire was used to obtain data on baseline characteristics and CT-related participant information. RESULTS: Of the 16,546 participants, 64.79% were women, with a mean age of 31.85 ± 7.31 of all participants. Of the participants, 88.78% were willing to undergo routine CT screening. According to multivariate logistic regression analyses, willingness to undergo routine CT screening was associated with the following (P < 0.05): being a woman (AOR = 1.53, 95% CI = 1.34-1.75), one year or more residency in Shenzhen (AOR = 1.64, 95% CI = 1.37-1.95), any secondary education (AOR = 2.46, 95% CI = 1.92-3.15), monthly income ≥ RMB 10,000 (AOR = 1.24, 95% CI = 1.01-1.51), having forgotten CT diagnosis history (AOR = 1.42, 95% CI = 1.12-1.79), without current STI-related symptoms (AOR = 1.24, 95% CI = 1.10-1.41), and having correct understanding of the sequelae of CT infection (AOR = 1.68, 95% CI = 1.39-2.03). CONCLUSION: This study reported high willingness to undergo routine CT screening among hospital-based patients in Shenzhen, and provided evidence for the promotion and the implementation of strategies and recommendations on routine CT screening in China.

High Willingness to Participate in Partner Notification among Women Attending Reproductive Health and STI Clinics in Shenzhen, China: A Cross-Sectional Study.

Genital Chlamydia trachomatis (CT) is one of the most common sexually transmitted infections (STI) worldwide. We explored the factors associated with willingness to participate in partner notification (PN) among women attending reproductive health and STI clinics in Shenzhen, China. An anonymous questionnaire was used to collect the sociodemographic characteristics, STI histories, and willingness to participate in routine CT screening and partner notification. In total, 87.31% (n = 10,780) of participants were willing to notify their sex partner(s) if they were diagnosed with a CT infection. Willingness to complete PN was significantly associated with: being married, residing in Shenzhen ≥1 year, having completed junior college or higher, not currently reporting STI-related symptoms, willing to have routine CT screening, and having a correct understanding of the health sequelae of CT infection. Nearly all women surveyed at reproductive health and STI clinics in Shenzhen reported willingness to complete PN. Promoting PN in these settings could help detect a large number of additional CT cases. Our findings provide evidence and implications for public health interventions on PN and suggest that targeted interventions are urgently needed for particular subpopulations including those not currently married, with shorter residency, lower education, and less awareness about the dangers of CT infection.

Compare HIV/syphilis infections between age groups and explore associated factors of HIV/syphilis co-infections among men who have sex with men in Shenzhen, China, from 2009 to 2017.

The aim of this study is to assess the HIV/syphilis epidemic among men who have sex with men (MSM) aged <50 years and ≥50 years in Shenzhen, and explore the associated factors of HIV/syphilis co-infections among MSM in Shenzhen, in order to help prevention and intervention programs determine their target sub-group. A serial cross-sectional study was conducted on MSM in Shenzhen city, China from 2009 to 2017. A questionnaire was used to collect demographic characteristics, history of HIV testing, history of blood donation and sexual behaviors. 5 ml of venous blood were collected for syphilis and HIV tests. The overall prevalence of HIV, syphilis, HIV/syphilis co-infection was 9.40%, 18.97%, and 4.91%, respectively. The prevalence of HIV (15.26%), syphilis (27.71%), HIV/syphilis co-infection (9.24%) in aged ≥50 years MSM was significantly higher than aged <50 years MSM (9.15%, 18.59% and 4.72%, respectively). The following factors were found to be significantly associated with HIV/syphilis co-infections (P<0.05): age≥50 years (OR = 1.78, 95% CI = 1.10-2.87), high school or lower (OR = 1.49, 95% CI = 1.10-2.01), monthly income ≤436.2 USD (OR = 1.74, 95% CI = 1.25-2.42), monthly income 436.4-727.2 USD (OR = 1.46, 95% CI = 1.05-2.03), ≥2 anal sex partners in the past 6 months (OR = 1.59, 95% CI = 1.02-2.49), ≥2 oral sex partners in the past 6 months (OR = 1.60, 95% CI = 1.08-2.36), inconsistent condom use during anal sex in the past 6 months (OR = 1.50, 95% CI = 1.11-2.03). We found that aged <50 years and ≥50 years MSM in Shenzhen had a high prevalence of HIV/syphilis infection in a period from 2009 to 2017. Age-specific sexually transmitted diseases education, prevention, and intervention programs for aged ≥50 years MSM should be implemented urgently and integrated interventions of both HIV and syphilis infections on MSM are needed in the future.

Correction: Population-based study of chlamydial and gonococcal infections among women in Shenzhen, China: Implications for programme planning.

[This corrects the article DOI: 10.1371/journal.pone.0196516.].

Population-based study of chlamydial and gonococcal infections among women in Shenzhen, China: Implications for programme planning.

This study was aimed to estimate the prevalences of chlamydia (CT) and gonococcal (NG) infections and explore risk factors associated with the CT infection among women in Shenzhen, China. We collected socio-demographic and clinical data from women (aged 20-60) and determined positivity of CT or NG by nucleic acid amplification test (NAAT) with self-collected urine specimens. We estimated prevalence of CT and NG and determined risk factors associated with CT infection. Among 9,207 participants, 4.12% (95% confidence interval [CI], 3.71%-4.53%) tested positive for CT and 0.17% (95% CIs, 0.09%-0.25%) for NG. Factors significantly associated with CT infection included being an ethnic minority (ethnicity other than Han China) (Adjusted odds ratio [AOR], 1.9; 95% CI, 1.2-3.0), using methods other than condom for contraception (AOR, 1.5; 95% CI, 1.2-1.8), having a history of adverse pregnancy outcomes (AOR, 1.4; 95% CI, 1.1-1.8), and experiencing reproductive tract symptoms in the past three months (AOR, 1.3; 95% CI, 1.0-1.7). we found that CT infection is prevalent among women in Shenzhen, China and associated with both demographic and behavioral factors. A comprehensive CT screening, surveillance and treatment programme targeting this population is warranted.

Risk of Congenital Syphilis (CS) Following Treatment of Maternal Syphilis: Results of a CS Control Program in China.

Background: Early screening for syphilis among pregnant women and the effective treatment of maternal syphilis is fundamental to prevent congenital syphilis (CS). Methods: We obtained data from the Shenzhen Program for Prevention of CS (SPPCS) and estimated incidence rates of CS among infants born to syphilis-seropositive women treated with different regimens or untreated for maternal syphilis. Results: A total of 4746 matched cases of syphilis-seropositive mothers and their infants were included for analyses, and 162 infants were diagnosed with CS, providing an overall incidence of 3.41% (95% confidence interval [CI], 2.91%-3.98%). Among infants born to syphilis-seropositive women who had syphilis and were adequately treated before pregnancy, the incidence was 0.22% (95% CI, .05%-.66%). There were 159 cases of CS occurring in 3519 infants born to women who were syphilis-seropositive during their pregnancies, for an incidence of 4.52% (95% CI, 3.84%-5.28%). The incidence of CS was 1.82%-11.90% lower among infants born to the women treated with early benzathine penicillin G (BPG) compared with those treated with late BPG (adjusted odds ratio [aOR], 8.06 [95% CI, 2.93-22.21]; P < .001), other antibiotics (aOR, 7.71 [95% CI, .86-69.28]; P = .068), or those untreated (aOR, 68.28 [95% CI, 29.64-157.28]; P < .001). The incidence rates were 0.22% (95% CI, .06%-.80%) and 0.59% (95% CI, .35%-1.02%) in infants born to women treated with 2 courses and 1 course of BPG, respectively, corresponding to a risk difference of 0.37% (aOR, 1.74; 95% CI, .37-8.26). Conclusions: Treatment of syphilis-seropositive pregnant women with 1 course of intramuscular BPG before 28 gestational weeks is critical for prevention of CS.

Prevalence of HIV and syphilis co-infection and associated factors among non-commercial men who have sex with men attending a sexually transmitted disease clinic in Shenzhen, China.

BACKGROUND: Although HIV and syphilis co-infection has been frequently observed in men who have sex with men (MSM), only few studies have focused on it. Different subgroups of MSM might exhibit heterogeneous HIV and syphilis risk profiles, indicating that interventions for HIV and HIV-related co-infections may vary with different subgroups of MSM. However, no previous study has investigated HIV and syphilis co-infection among non-commercial MSM (ncMSM) attending a sexually transmitted disease (STD) clinic. Therefore, this study aimed to explore the prevalence of HIV and syphilis co-infection and associated factors among ncMSM attending an STD clinic in Shenzhen, China. METHODS: NcMSM attending the STD clinic of Shenzhen Center for Chronic Disease Control were recruited in this cross-sectional study every Monday between March 2013 and August 2015 using a site based convenience sampling method. An anonymous questionnaire was used to collect data regarding socio-demographic characteristics, risky sexual behaviors and HIV-related knowledge. Blood samples were collected to perform HIV and syphilis tests. RESULTS: Totally 533 participants were enrolled in this study and the prevalence of HIV and syphilis co-infection among them was 13.13%. Multivariable analyses indicated that having lived in Shenzhen for less than one year (aOR = 2.80, 95% CI = 1.30-6.05), having first anal sexual intercourse before the age of 18 (aOR = 2.78, 95% CI = 1.29-5.89), having 3 to 5 anal sexual partners in the past six months (aOR = 2.54, 95% CI = 1.19-5.40), playing exclusively receptive (aOR = 6.87, 95% CI = 3.02-15.61) or both insertive and receptive (aOR = 3.65, 95% CI = 1.64-8.09) roles in anal sexual intercourse and not always using condom in anal sexual intercourse (aOR = 2.13, 95% CI = 1.08-4.19) were associated risk factors for HIV and syphilis co-infection, relative to the non-infected ncMSM. Compared with the mono-infected ncMSM, associated risk factors for the co-infection were being unmarried (aOR = 2.47, 95% CI = 1.03-5.89) and playing exclusively receptive role (aOR = 2.44, 95% CI = 1.04-5.73) in anal sexual intercourse. CONCLUSIONS: HIV and syphilis co-infection is quite prevalent among the study participants in Shenzhen. Integrated and intensified intervention strategies, specifically targeting at the non-infected and mono-infected ncMSM attending the STD clinic, are needed to reduce HIV and syphilis co-infection. Most importantly, non-infected and mono-infected ncMSM attending the STD clinic with the aforementioned associated risk factors should be given special concern.

Poor awareness of syphilis prevention and treatment knowledge among six different populations in south China.

BACKGROUND: China is facing an emerging epidemic of syphilis, and the cities in south China are most affected. Knowledge is a key factor in the prevention of syphilis infection, however, little is reported about how much people know about syphilis. This study was aimed at assessing peoples' awareness status in a city located in south China. METHODS: Six populations were recruited for this study, including urban residents, factory workers, college students, pregnant women, female sex workers (FSWs), and men who have sex with men (MSM). A questionnaire designed by the National Center for Disease Control and Prevention was used to assess participants' awareness of syphilis knowledge. About 5% of participants were randomly selected to conduct a telephone survey for confirming the validity of fieldwork. RESULTS: The study recruited 3470 participants, and 61.2% of participants were assigned to the awareness group. College students had the smallest percentage of awareness at 51.7% (371/718), followed by FSWs at 53.9% (200/371), factory workers at 56.0% (381/679), urban residents at 65.4% (435/665), pregnant women at 66.0% (451/683), and MSM at 81.1% (287/354). Multivariate logistic regression analysis showed that MSM and FSWs-but not factory workers and pregnant women-had more awareness of syphilis knowledge when comparing with urban residents; however, college students presented less awareness of syphilis knowledge than urban residents. Participants of younger age, of female gender, with lower education levels and without Shenzhen hukou possessed less awareness of syphilis knowledge than those of older age, of male gender, with higher education levels and with Shenzhen hukou respectively. CONCLUSIONS: The percentages of awareness on syphilis knowledge found in this study are far from the benchmark set in the national 10-year plan. Tailored interventions for different subgroups to increase syphilis awareness are urgently warranted.

Analysis of the sex ratio of reported gonorrhoea incidence in Shenzhen, China.

OBJECTIVE: To assess the clinical process of gonorrhoea diagnosis and report in China, and to determine the difference of sex ratio between reported incidence based on reporting data and true diagnosis rate based on reference tests of gonorrhoea. SETTING: A total of 26 dermatology and sexually transmitted disease (STD) departments, 34 obstetrics-gynaecology clinics and 28 urology outpatient clinics selected from 34 hospitals of Shenzhen regarded as our study sites. PARTICIPANTS: A total of 2754 participants were recruited in this study, and 2534 participants completed the questionnaire survey and provided genital tract secretion specimens. There were 1106 male and 1428 female participants. Eligible participants were patients who presented for outpatient STD care at the selected clinics for the first time in October 2012 were at least 18 years old, and were able to give informed consent. OUTCOME MEASURES: Untested rate, true-positive rate, false-negative rate and unreported rate of gonorrhoea, as well as reported gonorrhoea incidence sex ratio and true diagnosis sex ratio were calculated and used to describe the results. RESULTS: 2534 participants were enrolled in the study. The untested rate of gonorrhoea among females was significantly higher than that among males (female 88.1%, male 68.3%, p=0.001). The male-to-female sex ratios of untested rate, true-positive rate, false-negative rate and unreported rate were 1:1.3, 1.2:1, 1:1.6 and 1:1.4, respectively. The reported gonorrhoea incidence sex ratio of new diagnosed gonorrhoea was 19.8:1 (male vs female: 87/1106 vs 5/1420), while the true diagnosis sex ratio was 2.5:1 (male vs female: 161/1106 vs 84/1420). These data indicate that the sex ratio of reported gonorrhoea incidence has been overestimated by a factor of 7.9 (19.8/2.5). CONCLUSIONS: We found the current reported gonorrhoea incidence and sex ratios to be inaccurate due to underestimations of gonorrhoea incidence, especially among women.

Analysis of the Association between Catechol-O-Methyltransferase Val158Met and Male Sexual Orientation.

INTRODUCTION: Male sexual orientation is thought to have a genetic component. However, previous studies have failed to generate positive results from among candidate genes. Catechol-O-methyltransferase (COMT), located on chromosome 22, has six exons, spans 27 kb, and encodes a protein of 271 amino acids. COMT has an important role in regulating the embryonic levels of catecholamine neurotransmitters (such as dopamine, norepinephrine, and epinephrine) and estrogens. COMT is also thought to be related to sexual orientation. AIMS: This study aimed to investigate the relationship between the COMT Val158Met variant and male sexual orientation. We performed association analysis of the COMT gene single nucleotide polymorphism, Val158Met, in 409 homosexual cases and 387 heterosexual control Chinese men. COMT polymorphism status was determined using a polymerase chain reaction-based assay. METHODS: Polymerase chain reaction was performed to genotype the COMT Val158Met polymorphism. MAIN OUTCOME MEASURES: The frequency differences of the genotype and alleles distribution between the male homosexual and control groups. RESULTS: Significant differences, both in genotype and alleles, between male homosexual individuals and controls indicated a genetic component related to male homosexuality. The Val allele recessive model could be an interrelated genetic model of the cause of male homosexuality. CONCLUSION: The COMT Val158Met variant might be associated with male sexual orientation and a recessive model was suggested.

[Contact tracing of pregnant women infected with syphilis and the associated factors].

OBJECTIVE: To investigate the current status of contact tracing among pregnant women infected with syphilis and to analyze the associated factors from patients' perspective. METHODS: Pregnant women who aged 18 years old, receiving prenatal care services in Shenzhen, diagnosed with syphilis according to national diagnostic criteria (WS 273-2007) from 2008 to 2011 were recruited and the total number was 3 551. Information of both pregnant women (including demographic information, laboratory results, syphilis diagnosis, and personal life history) and their partners (including results of partner tracing and laboratory examination) were collected with structured questionnaire by face-to-face interview. Multivariate non-conditional logistic regression model was applied to analyze the factors associated with partners' contract tracing. Odds ratio (OR) and its 95% confidential interval (95%CI) were calculated. RESULTS: The average age was 28.72 among recruited 3 551 syphilis-infected pregnant women, with standard deviation of 5.21 and range of 18 to 40. Totally 2 550 partners attended antenatal clinics and received syphilis examination, with a contact tracing rate of 71.81%. The OR(95%CI) was 1.70(1.26-2.30) for pregnant women with college or above education when comparing with those with senior high school or below education. The OR(95%CI) was 0.57(0.45-0.71) for those unmarried or divorce when comparing with those married. The OR (95% CI) was 0.73(0.56-0.94) and 0.65(0.53-0.81) for those screened in 28-36 gestational weeks and those screened in >36 gestational weeks or right before delivery separately, when comparing with those screened in ≤27 gestational weeks. The OR (95% CI) was 1.45(1.14-1.84) for those having received sufficient treatment before pregnancy when comparing with those diagnosed with latent syphilis. The OR(95%CI) was 0.31 (0.24-0.39) for those having no treatment or not standardized treatment when comparing with those having standardized penicillin treatment. The OR(95%CI) was 0.53 (0.43-0.65) for those terminating the pregnancy when comparing with those giving birth to a baby. The OR(95%CI) was 1.24 (1.05-1.46) for those having two or more love histories when comparing with those having only one love history. The OR(95%CI) was 4.74 (3.54-6.35) for those intending to disclose the serostatus to their partner when comparing with those showing unwillingness to disclose the serostatus. CONCLUSION: The successful rate of contact tracing among pregnant women infected with syphilis was high. The implementation of contact tracing may be affected by many factors, including patients' education levels, marital status, gestational weeks of screening, stage of syphilis, treatment status, outcome of pregnancy, number of love histories, and willingness of serostatus disclosure.

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).

[Factors associated with HIV and syphilis infection among men who have sex with men blood donors in Shenzhen].

OBJECTIVE: To investigate the distribution and factors associated with HIV and syphilis infection among Men who have sex with men blood donors (MSMBD) in Shenzhen. METHODS: A total of 813 MSMBD were recruited using snowball sampling and respondent driven sampling from 2009 to 2012 in Shenzhen. Questionnaire-based interviews were conducted on a one-on-one basis. Data were collected including socio-demographic information, HIV testing history, self-identified sexual orientation, role in homosexual behavior, information about having sex with male sexual partners in the past six months and information about having sex with female sexual partners in the past six months.5 ml blood samples were taken and tested for treponema pallidum and HIV antibodies. Comparisons of syphilis and HIV infection among different years were analyzed by the Cochran-Armitage trend test. Factors associated with syphilis and HIV infection were analyzed by the univariate logistic regression and multivariate unconditional logistic regression. RESULTS: The prevalence of syphilis, HIV, and syphilis-HIV co-infection among 813 participants were 22.0% (179/813), 8.0% (65/813), and 4.2% (34/813), respectively. In the multivariate logistic regression analysis, ever tested for HIV (versus without HIV testing history, OR (95%CI) = 0.369(0.213-0.641)) will decrease the risk of HIV infection among MSMBD in comparison with never tested for HIV (OR (95%CI) = 0.37 (0.21-0.64) ); having five or more anal sexual partners in the past six months and co-infected with syphilis will increase the risk of HIV infection among MSMBD in comparison with having 0-1 sexual partners (OR (95%CI) = 2.04 (1.03-4.06) ) and negative syphilis (OR (95%CI) = 4.52(2.64-7.73)), respectively, bisexual orientation, having 2-4 anal sexual partners and having five or more anal sexual partners in the past six months, using condoms not for every act of anal sex, co-infected with HIV will increase the risk of syphilis infection among MSMBD in comparison with homosexual orientation (OR (95%CI) = 1.60(1.12-2.27)), having 0-1 sexual partner in the past six months (OR (95%CI) = 1.77 (1.09-2.87) and OR (95%CI) = 1.84(1.09-3.08) ) , using condoms for every act of anal sex (OR (95%CI) = 1.61 (1.10-2.36) ) and negative HIV (OR (95%CI) = 4.02 (2.33-6.96)), respectively. CONCLUSION: The prevalence of HIV and syphilis among MSMBD in Shenzhen are much higher with complex influence factors. The relevant government should pay great attention to it and ensure the blood safety.

Reduction in mother-to-child transmission of syphilis for 10 years in Shenzhen, China.

BACKGROUND: Untreated maternal syphilis can result in the fetuses being infected. Severe adverse pregnancy outcomes include stillbirth, perinatal death, low birth weight, and congenital syphilis (CS). The World Health Organization has already classified global elimination of CS as a priority. However, this preventable disease is still threatening people's health in the world. METHODS: A Programme of Prevention of Mother-to-Child Transmission of Syphilis in Shenzhen was launched in 2002. All pregnant women in Shenzhen were screened for syphilis by serological methods at their first prenatal care visit. The infected individuals were treated with 3 weekly injections of 2.4 million units of benzathine penicillin. The babies were followed up until 18 months old to diagnose CS. RESULTS: Up to 2011, the Programme of Prevention of Mother-to-Child Transmission of Syphilis in Shenzhen screened 2,077,362 pregnant women and intervened in 7668 mothers infected with syphilis. The screened rate among pregnant women increased from 89.8% in 2002 to 97.4% in 2011. The proportion of those having adverse pregnant outcomes (including spontaneous abortion, premature delivery, and stillbirth) decreased from 27.3% in 2003 to 8.2% in 2011. The incidence of CS decreased from 115/100,000 in 2002 to 10/100,000 (live births) in 2011. CONCLUSIONS: In 2002, in the face of rising CS numbers, Shenzhen adapted a syphilis control program that involved cost-free testing for pregnant women, commitment and collaboration at multiple levels of the health system, and strong supervision and government guidance. Local program and surveillance data suggest that the program has been very successful in reducing CS incidence.

Risk factors for congenital syphilis and adverse pregnancy outcomes in offspring of women with syphilis in Shenzhen, China: a prospective nested case-control study.

BACKGROUND: Despite existence of a highly effective intervention, maternal syphilis still causes substantial perinatal morbidity and mortality, even in China, where antenatal health services are strong. This study sought to address personal, programmatic, and other risk factors for congenital syphilis (CS) and adverse pregnancy outcomes (APOs) among pregnant women in Shenzhen, China. METHODS: Pregnant women attending antenatal services were offered serologic tests, and those diagnosed as having syphilis were recruited from April 2007 to October 2012. In a nested case-control study for the pregnancy outcomes of syphilis-infected women, we assessed risk factors comparing infants born with CS (group II) and with any APOs (group III) to infants without CS or APOs (group I). RESULTS: During the 66-month study period, we screened 279,334 pregnant women and identified 838 (0.3%; 95% confidence interval, 0.28%-0.32%) women infected with syphilis. Among infants born to syphilitic mothers, 8.2% (34/417) were diagnosed as having CS and 24.7% (103/417) were diagnosed as having APOs. Compared with group I, maternal baseline titers of nontreponemal antibodies (adjusted odds ratio [aOR], 2.13), stage of syphilis (aOR, 21.56), length of time between the end of the first treatment to childbirth (aOR, 11.93), gestational week at treatment (aOR, 2.63), and fathers' cocaine use (aOR, 15.44) and syphilis infection status (aORpositive vs. negative, 5.84; aORunknown vs. negative, 5.55) were positively associated with CS, but prenatal care (aOR, 0.11) and complete treatment (aOR, 0.20) were negatively associated with CS. Maternal age (aOR, 1.43), marriage (aOR, 2.41), history of cocaine use (aOR, 3.79) and ectopic pregnancy (aOR, 5.91), baseline titers of nontreponemal antibodies (aOR, 1.30), stage of syphilis (aOR, 8.89), length of time between the end of the first treatment to childbirth (aOR, 2.52), gestational week at treatment (aOR, 1.78), and fathers' syphilis infection status (aORunknown vs. negative, 2.02) were also positively associated with APOs, but maternal history of syphilis (aOR, 0.44), prenatal care (aOR, 0.29), and complete treatment (aOR, 0.25) were negatively associated with APOs, CONCLUSIONS: Syphilis was an important cause of pregnancy loss and infant disability, particularly among women who did not receive prenatal care or had late or inadequate treatment. These study results can inform antenatal programs on the importance of early syphilis testing and prompt and appropriate treatment. Some strategies targeted at other risk factors areas may be helpful.

Mediation effect of perceived behavioural control on intended condom use: applicability of the theory of planned behaviour to money boys in China.

BACKGROUND: Money boys (MBs) are male sex workers who sell sex to men who have sex with men. The objectives of this study were to assess (a) the sexual HIV risk of MBs; (b) the ability of the theory of planned behaviour (TPB) to predict MBs' intentions to use condoms; and (c) the manner in which TPB constructs (attitudes towards condom use, subjective norms and perceived behavioural control) combine to influence condom use intentions. METHODS: Participants came from 10 MB-frequented clubs in two cities in China. Multiple regression and path analytic models were used to test inter-relationships among the TPB constructs. RESULTS: Seventy-eight percent of the 122 MB participants reported having used condoms for every anal sex act. About one-third reported having had female sexual partners in the past 2 months; of these MBs, half (53%) used condoms for every sex act. A revised model using TPB constructs accounted for 52% of the variance of condom use intentions and revealed that perceived behavioural control was a mediator in pathways beginning with attitudes and ending with condom use intentions, and beginning with subjective norms and ending with intentions. CONCLUSIONS: The findings suggest that a revised model of TPB applies to condom use intentions among Chinese MBs. It may be appropriate to adapt HIV interventions that are grounded in TPB and that have been shown to be effective elsewhere for use with Chinese MBs. HIV interventions for this population should give perceived behavioural control and its predictors special consideration.

[Primary drug resistance of HIV-1 infected men who have sex with men in Shenzhen, China].

OBJECTIVE: To evaluate the status of drug resistance among treat-naive HIV-1 infected men who have sex with men (MSM) in Shenzhen during the period of 2008 - 2010. METHODS: Plasma samples of 227 treatment-naive HIV-1 infected MSM were collected in Shenzhen. HIV-1 pol genes (RT and PR) were amplified by nested-polymerase chain reaction (PCR) from RNA. Phylogenetic and drug resistance analyses were performed on the nucleotide sequence data. RESULTS: A total of 164 pol gene sequences were amplified. The prevalence of primary genotypic drug resistance was 14.6%. The overall prevalence of drug-resistant mutations was 22.6%, corresponding to 8.54% for protease inhibitors (PI) minor drug resistance mutation, 1.22% for nucleotide reverse transcriptase inhibitors (NRTI) drug resistance mutation and 13.41% for non-nucleotide reverse transcriptase inhibitors (NNRTI) drug resistance mutation. The prevalence of drug-resistant mutations was 30.88% for CRF01_AE strain and 19.23% for B strain. CONCLUSION: The prevalence of drug resistance is relatively moderate in the treat-naive HIV-1 infected MSM in Shenzhen. The prevalence of drug-resistant HIV-1 among MSM in Shenzhen should raise a high alert.

[Study on the molecular-epidemiological characteristics of HIV-1 in Shenzhen, 1992-2008].

OBJECTIVE: To investigate the epidemiological characteristics of HIV-1 subtype in Shenzhen from 1992 to 2008. METHODS: 489 HIV-1 positive plasma samples were collected from 1992 to 2008 in Shenzhen. HIV-1 env genes were amplified by nested-PCR from RNA. Phylogenetic analysis was performed on data regarding the nucleotide sequence. RESULTS: A total of 464 sequences were amplified and genotyped. Data from this study revealed that CRF01_AE was a predominant HIV-1 subtype in Shenzhen (64.4%, 299/464), followed by subtypes CRF_BC (17.5%, 81/464), B' (14.7%, 68/464) and B (2.4%, 11/464). Subtype C (0.4%, 2/464), A1 (0.2%, 1/464), CRF02_AG (0.2%, 1/464) and CRF06_cpx (0.2%, 1/464) were also prevalent in Shenzhen. CRF01_AE and CRF_BC were predominant among heterosexuals, homosexuals and injection drug users, while B' was predominant among blood donors. Results from phylogenetic tree analysis showed that some of the HIV-1 clusters had been defined in CRF01_AE strains at different time or groups with different transmission routes. Cross-infections were also seen. CONCLUSION: CRF01_AE was the predominant HIV-1 subtype in Shenzhen while CRF_BC, B, B', C, A1, CRF02_AG and a small amount of CRF06_cpx or recombinant subtypes were prevalent in this city. Different subtypes showed great variation in the process of epidemics.

Multilevel and spatial analysis of syphilis in Shenzhen, China, to inform spatially targeted control measures.

OBJECTIVES: The present study investigates the varied spatial distribution of syphilis cases in Shenzhen, China, and explores the individual-, neighbourhood- and district-level factors affecting the distribution. METHODS: This study uses spatial analysis and multi-level generalised estimating equations to explore the spatial distribution of reported syphilis cases among individuals in Shenzhen, Guangdong Province, China. The spatial distribution of primary/secondary and latent cases was investigated using the Moran's I-statistic. Primary/secondary syphilis cases were compared with all syphilis cases using a three-level model with individual (n=6496), neighbourhood (n=55) and district (n=6) levels. RESULTS: A total of 6496 syphilis cases were reported in 2009 with 35.8% primary and secondary syphilis cases. Both primary/secondary syphilis cases (Moran's I value=0.33, p<0.01) and latent syphilis cases (Moran's I value=0.19, p<0.01) showed significant spatial clustering at the neighbourhood level. Adjusting for the number of reporting hospitals, the best model found that the following characteristics were associated with primary/secondary syphilis infection: individuals who are younger in age (p=0.003), male (p<0.001), migrant labourers (p=0.047) and those who live in districts with a higher gross domestic product (p<0.001). CONCLUSIONS: There is substantial clustering of primary and secondary syphilis cases at the neighbourhood level in Shenzhen, suggesting the need for greater STD health service provision in these clustered neighbourhoods. Spatially targeted syphilis control measures may be useful to optimise testing, treatment and partner services.