Seroepidemiology of Syphilis Infection among 2 Million Reproductive-age Women in Rural China: A Population-based, Cross-sectional Study.

BACKGROUND:: Quantifying syphilis prevalence is important for planning interventions and advocating for resources on syphilis. However, data on large sample studies regarding the prevalence of syphilis among reproductive-age women in rural China were not available for analysis. The aim of the study was to determine the prevalence, epidemiological characteristics, and related factors of syphilis infection among reproductive-age women in rural China. METHODS:: Data were obtained from a nationwide, population-based, cross-sectional study under the National Free Preconception Health Examination Project which covered all the 31 provinces in Mainland China. Women intending to get pregnant within the next 6 months were enrolled between January 1, 2010, and December 31, 2012. Sociodemographic, gynecological and obstetric characteristics, and other relevant information were obtained through face-to-face interviews. Treponema pallidum particle agglutination assay test was used to detect positive samples of syphilis. Univariate and multivariate logistic regressions were performed to assess the associations between syphilis seropositivity and related factors. RESULTS:: The overall seroprevalence of syphilis (SPS) among the 2,044,126 women who received syphilis screening test during 2010-2012 was 0.37% (95% confidence interval [CI]: 0.36-0.37%). The SPS appeared 0.24% (95% CI: 0.23-0.26%) and 0.66% (95% CI: 0.59-0.72%) in women at 21-24 and 40-44 years of age, respectively, showing an increase of SPS, parallel with age, and the difference was significant. SPS was significantly higher in ethnic minorities than that in Han nationality (0.58% vs. 0.35%, respectively, odds ratio [OR] = 1.41, 95% CI: 1.30-1.53) and higher in workers than that in farmers (0.45% vs. 0.36%, respectively, OR = 1.27, 95% CI: 1.14-1.41). Women with primary school or below level had a higher SPS as compared to those with college or above educational level (0.61% vs. 0.32%, respectively, OR = 2.49, 95% CI: 2.14-2.89), and the increase reversely correlated with the levels of education. Women whose spouses were syphilis seropositive had significant greater risk (OR = 48.26, 95% CI: 44.38-52.48) as compared those whose spouses were seronegative. Women who reported having had a history of sexually transmitted infections were more likely to be tested positive for serological syphilis (OR = 27.17, 95% CI: 20.44-36.11) as compared to those without. CONCLUSIONS:: High SPS is seen among reproductive-age women in rural China that calls for targeted interventions on syphilis prevention and control in this target population, with emphasis on those who are 35 years of age and above, less educated, being minor ethnicity, workers, and living in the western regions of China.

Do mutations in DNMT3A/3B affect global DNA hypomethylation among benzene-exposed workers in Southeast China?: Effects of mutations in DNMT3A/3B on global DNA hypomethylation.

Global DNA hypomethylation is commonly observed in benzene-exposed workers, but the underlying mechanisms remain unclear. We sought to discover the relationships among reduced white blood cell (WBC) counts, micronuclear (MN) frequency, and global DNA methylation to determine whether there were associations with mutations in DNMT3A/3B. Therefore, we recruited 410 shoe factory workers and 102 controls from Wenzhou in Zhenjiang Province. A Methylated DNA Quantification Kit was used to quantify global DNA methylation, and single nucleotide polymorphisms (SNPs) in DNMT3A (rs36012910, rs1550117, and R882) and DNMT3B (rs1569686, rs2424909, and rs2424913) were identified using the restriction fragment length polymorphism method. A multilinear regression analysis demonstrated that the benzene-exposed workers experienced significant global DNA hypomethylation compared with the controls (ß = -0.51, 95% CI: -0.69 to -0.32, P < 0.001). The DNMT3A R882 mutant allele (R882H and R882C) (ß = -0.25, 95% CI: -0.54 to 0.04, P = 0.094) and the DNMT3B rs2424909 GG allele (ß = -0.37, 95% CI: -0.70 to -0.03, P = 0.031) were significantly associated with global DNA hypomethylation compared with the wild-type genotype after adjusting for confounding factors. Furthermore, the MN frequency in the R882 mutant allele (R882H and R882C) (FR = 1.18, 95% CI: 0.99 to 1.40, P = 0.054) was higher than that of the wild-type. The results imply that hypomethylation occurs due to benzene exposure and that mutations in DNMTs are significantly associated with global DNA methylation, which might have influenced the induction of MN following exposure to benzene. Environ. Mol. Mutagen. 58:678-687, 2017. © 2017 Wiley Periodicals, Inc.

Risk factors for influenza A(H7N9) disease--China, 2013.

BACKGROUND: The majority of human cases of novel avian influenza A(H7N9), which emerged in China in spring 2013, include reported exposure to poultry. However, specific host and exposure risk factors for disease are unknown, yet critical to design prevention measures. METHODS: In April-June 2013, we conducted a case-control study in 8 Chinese provinces. Patients with laboratory-confirmed A(H7N9) (n = 89) were matched by age, sex, and neighborhood to controls (n = 339). Subjects completed a questionnaire on medical history and potential exposures, including poultry markets and other poultry exposure. We used conditional logistic regression to calculate matched and adjusted odds ratios (ORs) for the association of A(H7N9) virus infection with potential risk factors. RESULTS: Fifty-five percent of patients compared with 31% of controls reported any contact with poultry (matched OR [mOR], 7.8; 95% confidence interval [CI], 3.3-18.8). Sixty-seven percent of patients compared with 35% of controls visited a live poultry market (mOR, 5.4; CI, 3.0-9.7). Visiting live poultry markets increased risk of infection even after adjusting for poultry contact and other confounders (adjusted OR, 3.4; CI, 1.8-6.7). Backyard poultry were not associated with increased risk; 14% of cases did not report any poultry exposure or market visit. Obesity (mOR, 4.7; CI, 1.8-12.4), chronic obstructive pulmonary disease (mOR, 2.7; CI, 1.1-6.9), and immunosuppressive medications (mOR, 9.0; CI, 1.7-47.2) were associated with A(H7N9) disease. CONCLUSION: Exposures to poultry in markets were associated with A(H7N9) virus infection, even without poultry contact. China should consider permanently closing live poultry markets or aggressively pursuing control measures to prevent spread of this emerging pathogen.

Use of national pneumonia surveillance to describe influenza A(H7N9) virus epidemiology, China, 2004-2013.

In mainland China, most avian influenza A(H7N9) cases in the spring of 2013 were reported through the pneumonia of unknown etiology (PUE) surveillance system. To understand the role of possible underreporting and surveillance bias in assessing the epidemiology of subtype H7N9 cases and the effect of live-poultry market closures, we examined all PUE cases reported from 2004 through May 3, 2013. Historically, the PUE system was underused, reporting was inconsistent, and PUE reporting was biased toward A(H7N9)-affected provinces, with sparse data from unaffected provinces; however, we found no evidence that the older ages of persons with A(H7N9) resulted from surveillance bias. The absolute number and the proportion of PUE cases confirmed to be A(H7N9) declined after live-poultry market closures (p<0.001), indicating that market closures might have positively affected outbreak control. In China, PUE surveillance needs to be improved.