Spatiotemporal analysis of 11 years of Chlamydia trachomatis data from southern China

Chlamydia cases in women of reproductive age, 2006-2020: an analysis of surveillance data from Southern China

BACKGROUND

Chlamydia is common among women of reproductive age and can cause serious health issues. This study aimed to examine the trends and factors linked to newly diagnosed and reported chlamydia cases in women aged 15-49 in Guangdong Province from 2006 to 2020.

METHODS

We included all newly diagnosed and reported chlamydia cases from January 1, 2006, to December 31, 2020. Data from 21 cities in Guangdong Province were sourced from the National Notifiable Infectious Disease Reporting Information System in China. Temporal trends were analyzed using Joinpoint regression models. City-level factors (population density, net migration rate, and male-to-female sex ratio) were derived from the Guangdong Statistical Yearbook and the Guangdong Health and Family Planning Statistical Yearbook. Quasi-Poisson regression models were used to explore the relationship between sociodemographic factors and chlamydia incidence.

RESULTS

From 2006 to 2020, 523,367 new chlamydia cases were reported among women of reproductive age in Guangdong. The mean reported rate was 122.6 per 100,000 population over 15 years, significantly increasing from 1.4 in 2006 to 179.7 in 2020 (average annual percent change [AAPC] = 47.4%, 95% CI: 42.8%-52.2%, P < 0.05). The highest rate was 196.8 per 100,000 population in 2019. Among older women, 9,045 cases were reported, with a mean reported rate of 4.9 per 100,000, rising significantly from 0.01 in 2006 to 9.6 in 2020 (AAPC = 52.6%, 95% CI: 30.3%-78.8%, P < 0.05). The reported rate among women of reproductive age correlated with the net migration rate (RR = 1.2; 95% CI: 1.2-1.3) and the ratio of those participating in child-bearing insurance to the permanent population (RR = 1.5; 95% CI: 1.4-1.6).

CONCLUSION

The reported rate of new chlamydia cases among women of reproductive age was significantly higher than among older adults and increased markedly from 2006 to 2020. These findings underscore the urgent need for targeted prevention strategies for women of reproductive age.

Mapping gentrification, segregation, rental cost burden and sexually transmitted infections in Atlanta, Georgia, 2005-2018

Racial disparities in sexually transmitted infections (STIs) in the United States have been linked to social inequities. Gentrification instigates population-level shifts in housing markets and neighborhood racial/ethnic composition in ways that may impact the spatial distribution of STIs. This study assessed overlap in clusters of STIs, gentrification, social and economic disadvantage, and rental cost burden in Atlanta, Georgia, between 2005 and 2018. Overlap between gentrification and STIs among Black people was greater than that observed for the overlap between gentrification and STIs among White people. Overlap of STIs with social disadvantage and rental cost burden was more prominent among White people than Black people over time. Additional investigation into the factors behind the spatial dynamics observed in this study, and explanations for their variation by race, are necessary to inform where place-based efforts are targeted to reduce racial disparities in STI transmission in gentrifying cities.

Trends of chlamydia and gonorrhea infections by anatomic sites among men who have sex with men in south China: a surveillance analysis from 2018 to 2022

BACKGROUND

Chlamydia and gonorrhea notifications are rapidly rising in men who have sex with men (MSM). Currently, there are limited data on the prevalence of chlamydia and gonorrhea across various anatomical sites. Our study aimed to explore the prevalence, association and changing trends of urethral and rectal chlamydia and gonorrhea among MSM in Guangdong Province, China.

METHODS

We analyzed data among MSM attending sexually transmitted infections (STI) clinics in the Guangdong governmental sentinel network between 2018 and 2022. Chi-square tests were used to compare the difference, Join-point regressions for analyzing changing trends, and multivariate logistic regressions for examining associated factors.

RESULTS

We included 4856 men in the analysis. Rectal chlamydia significantly increased from 13.8% to 26.4% over the past 5 years (average annual percentage change [AAPC] 19.2%, 95%CI 1.0-40.6, p = 0.043). After adjusting for covariates, chlamydia infection positively associated with main venue used to seek sexual partners (aOR = 2.31, 95%CI 1.17-4.55), having regular sexual partners in the past 6 months (aOR = 3.32, 95%CI 1.95-5.64), receiving HIV counselling and testing services (aOR = 2.94, 95%CI 1.67-5.17), receiving peer education (aOR = 1.80, 95%CI 1.14-2.83), infection with syphilis (aOR = 2.02, 95%CI 1.02-4.01) and infection with gonorrhea (aOR 7.04, 95% CI 3.01-16.48). Gonorrhea infection positively associated with having regular sexual partners in the past 6 months (aOR = 3.48.95%CI 1.16-10.49), and infection with chlamydia (aOR 7.03, 95% CI 2.99-16.51).

CONCLUSIONS

To conclude, our findings reveal a high prevalence of chlamydia infections among MSM, particularly in the rectal area. Comprehensive chlamydia and gonorrhea health services are necessary for MSM to improve sexual health.

The prevalence and correlates of unintended pregnancy among female sex workers in South China: a cross-sectional study

BACKGROUND

Female sex workers (FSW) are particularly vulnerable to unintended pregnancy. Research examining the experience of unintended pregnancy due to commercial sex among Chinese FSW, however, is limited. This study aimed to examine the prevalence and correlates of unintended pregnancy due to commercial sex among FSW in China.

METHODS

In 2021, a cross-sectional study was conducted among 1257 FSW in five cities from Guangdong provinces in South China. Data were collected on social-demographic characteristics, sexual behaviors, experience of unintended pregnancy due to commercial sex and its pregnancy outcome, as well as experience of abortion in lifetime. Multivariable logistic regression analysis was employed to identify factors associated with unintended pregnancy.

RESULTS

Among the 1257 FSW, 19.3% reported having at least one unintended pregnancy due to commercial sex. Of those, 96.7% chose to terminate the pregnancy through induced abortion, and 40.5% reported undergoing multiple induced abortions in their lifetime. Multivariable logistic regression indicated that FSW working in current location over one year (adjusted Odds Ratio (aOR): 2.82, 95% CI 1.71-4.64) and having more than seven clients in the past week (aOR: 4.53, 95% CI 2.74-7.51) were more likely to have had unintended pregnancy due to commercial sex. Working in high tier (aOR: 0.21, 95% CI 0.14-0.30) and consistent condom use with clients in the past month (aOR: 0.16, 95% CI 0.10-0.23) were associated with a lower proportion of FSW having ever had unintended pregnancy.

CONCLUSIONS

Unintended pregnancy are prevalent among FSW in South China. Interventions aimed at reducing the prevalence of unintended pregnancy and enhancing post-abortion care could be necessary among Chinese FSW.

Emergence of Novel Chlamydia trachomatis Sequence Types among Chlamydia Patients in the Republic of Belarus

Chlamydia trachomatis (CT) is a major cause of sexually transmitted diseases worldwide. The multilocus sequence typing (MLST) of clinical samples from random heterosexual chlamydia patients who were either asymptomatic or reported clinical manifestations of genital chlamydiosis (n = 63) in each of the seven major regions of the Republic of Belarus in 2017–2018 revealed 12 different CT sequence types (STs). We found seven known STs, ST4, ST6, ST9, ST13, ST38, ST95 and ST110, and five novel variants, namely ST271–ST275, which have not been detected elsewhere thus far. The ST4 variant was predominant (27/63, 42.9%) and detected in six out of seven regions. The two most common STs, ST9 and ST13, were regularly seen in four out of seven regions. In contrast, the remaining STs, ST6, ST38, ST95, ST110, and novel STs271-275, surfaced randomly in different parts of the country. The emergence of novel STs was registered in two regions, namely Minsk (ST271 and ST275) and Brest (ST271, ST272, ST273, and ST274). All the STs of detected CT strains were clustered into two Groups, I and III, which are characteristic of CT urogenital strains. No STs typical for Group II, specific to the LGV strains, were revealed. Our study contributes to better understanding the genetic diversity and molecular evolution of CT, one of the most important pathogens in public health worldwide.

New Syphilis Cases in Older Adults, 2004-2019: An Analysis of Surveillance Data From South China

Background: Sexual health among older adults is a major public health concern globally. The syphilis burden is increasing in older adults in China. This study aimed to describe factors associated with syphilis infection and diagnosis among older adults in China during a 16 year period. Methods: Using 16 years of data (2004-2019) from the syphilis case report system of Guangdong, China, we compared data from older adults (aged ≥50 years) with those from younger people (aged 15-49 years). We compared the two age group with the Chi-square test for difference, and Joinpoint regression models to assess the temporal trends. Results: During the study period, 242,115 new syphilis diagnoses were reported in older adults. The mean notification rate of new diagnoses was 64.1 per 100,000 population across the entire 16-year period, which significantly increased over time (average annual percent change [AAPC] 16.2%, 95% CI 13.7-18.7). Syphilis diagnoses increased significantly over time among less developed cities and older women. In 2019, compared with younger adults, newly diagnosed older adults were more likely to be male, native to reporting city, had unknown transmission routes, and were diagnosed late. Conclusion: Our findings call for an urgent need to deliver more targeted prevention interventions for older adults, such as strengthen awareness among health care providers, and integration of syphilis services and primary health care for older adults.