Using Self-Reported Sexual Positioning as an Indicator for Rectal Chlamydia and Gonorrhea Screening Among Men Who Have Sex With Men in China: A Missed Opportunity.

BACKGROUND: Rectal Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections among men who have sex with men (MSM) are escalating public health concerns. This study aimed to explore (1) the reliability of self-reported sexual positioning as an indicator for rectal CT and NG screening, and (2) factors associated with rectal CT and NG infections in Shenzhen, China. METHODS: A cross-sectional study was conducted in 2 settings in Shenzhen, China, from April 1, 2021, to March 31, 2022. Data on sociodemographic characteristics, sexual behaviors, and basic CT knowledge were collected. Urine and self-collected rectal swabs were collected for CT and NG testing. RESULTS: In total, 195 MSM participated in the study, and 5.1% tested positive for urogenital CT, 29.2% for rectal CT, 1.0% for urogenital NG, and 8.2% for rectal NG. Among those who reported exclusively insertive anal sex, 69.2% of CT infections and 85.7% of NG infections would have remained undetected with urine testing alone. Risk factors for rectal CT infection included engaging in both insertive and receptive anal sex, with a significant association found for coinfection with rectal NG. CONCLUSIONS: Self-reported sexual positioning was found to be an unreliable indicator for CT and NG screening, as a substantial proportion of infections would have remained undetected. The findings suggest that CT and NG screening in China should be offered to all MSM regardless of self-reported sexual positioning, and that the dual CT/NG testing is recommended.

[Spatial and temporal patterns of primary and secondary syphilis in Shenzhen, China].

OBJECTIVE: To learn the spatial and temporal patterns of primary syphilis and secondary syphilis in Shenzhen and to provide evidence for carrying out further research on syphilis. METHODS: Primary syphilis and secondary syphilis cases among residents in Shenzhen between 2005 and 2009 (n = 11 303) were geocoded at street office level (n = 55) based on residence at the time of diagnosis. Both spatial and space-time scan statistics were used to identify clusters of street office by using SaTScan software. RESULTS: In the purely spatial analyses, clusters were seen in the junction of the Baoan district and Nanshan district (Xinan, Xixiang, Nanshan and Nantou street office) and in the region near Hong Kong (Dongmen, Shekou, and Futian street office), as well as in the other streets where entertainment industry was relatively developed (Longhua, Huafu, Huangbei and Cuizu street office). The clusters had not changed much in the first four years, but nine clusters appeared in 2009. Annually, the most likely clusters were located in Longhua (2005, P ≤ 0.001, RR = 3.34), Bamboo (2006, P ≤ 0.001, RR = 9.59), Huafu (2007, 2008 years, P ≤ 0.001, RR values were 4.18 and 4.75) and Cuizu (2009, P ≤ 0.001, RR = 8.02). In the space-time scan analysis, we found 16 significant clusters, which were similar to the pure spatial analyses. However, regional difference were also found, with the most likely cluster was the Guiyuan street office in 2006. CONCLUSION: Spatial and space-time scan statistics seemed to be effective ways in describing the circular disease clusters. We have had a better understanding on spatial and temporal patterns of primary syphilis and secondary syphilis in Shenzhen through spatial and space-time scan statistics of syphilis surveillance data in the recent years. The changes of spatial and temporal patterns of primary syphilis and secondary syphilis were also described by SaTScan software, which also provided useful reference for the preventive strategies on sexually transmitted diseases as well as on HIV. Useful information was also provided for financial investment and cost-effective studies.

A risk model for congenital syphilis in infants born to mothers with syphilis treated in gestation: a prospective cohort study.

OBJECTIVE: To explore the risk factors underlying congenital syphilis (CS) and to build a hazards model to assess the risk of CS in offspring born to mothers with syphilis treated in gestation. METHODS: This prospective study observed 554 pregnant women with syphilis and their offspring recruited from August 2002 to May 2007 in Shenzhen Centre for Chronic Disease Control and Prevention. After treatment, all the women were followed up until the diagnosis of CS in their offspring was confirmed or denied. Comparisons were made between women bearing infants with CS and women bearing infants without CS to reveal the risk factors for CS. ORs and their 95% CI were calculated for each risk factor by using logistical regression analysis. RESULTS: Twenty-nine (5.2%) infants were diagnosed with CS. Univariable analyses showed that the reciprocal logarithm of the titre of non-treponemal antibodies in mothers (log (1/T); OR=11.18, p<0.001), gestational week (GW) at treatment (OR=1.10, p<0.001) and the interaction between these two variates (OR=1.09, p<0.001) was associated with CS. Multivariable analysis showed that only the interaction was significantly associated with CS (OR=1.09, p=0.047). CONCLUSIONS: The risk of CS could be predicted by the interaction between GW x log (1/T). Early treatment given to women with syphilis during antenatal care may be the only effective method to decrease the risk of CS.