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

M. Kumi Smith, Kelly M. Searle, Wenyue Wang, Erica Rapheal, Cheng Wang, Peizhen Zhao, Ligang Yang, Shujie Huang, Bin Yang

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


Background: Urogenital Chlamydia trachomatis is the most prevalent bacterial sexually transmitted infection (STI) globally. Reviews suggest high and persistently endemic STI epidemics in low and middle income countries. However population-based prevalence estimates in these settings are less common, underscoring the need for analyses of available data to characterize patterns of disease burden. We identified spatio-temporal clusters and key behavioral, social, or environmental factors contribution to transmission in order to inform the prioritization and targeting of evidence based interventions. Methods: Using 11 years of data (2006–2016) from the chlamydia case report system of Guangdong, China, we identified county level spatio-temporal hot and cold spots using the Getis-Ord Gi* statistic and discrete Poisson models in SaTScan 9.6. We also estimated associations between observed distribution patterns and area-level demographic, social, and economic factors using quasi-Poisson regression models that controlled for annual counts of certified laboratories to account for fluctuations in location-specific detection capacity. Findings: Cluster analysis indicates an expanding chlamydia epidemic in Guangdong, with cases clustered in regions of greatest economic activity. Greater male-to-female sex ratio (RR, 3.63; 95% CI, 1.41–9.45) and greater urbanicity (RR, 2.44; 95% CI, 1.98–2.99) were predictive of higher chlamydia case occurrence. Interpretation: We found that chlamydia case occurrence in Guangdong province has been accelerating over the past 11 years and that its expansion is tied to indicators of social and economic development. These estimates not only identify high prevalence regions to target but also areas where data gaps potentially remain. The salience of sex ratios and urbanicity may best be understood through the lens of China's modern history of labor migration which has reshaped the gender dynamics and health access landscape of urban China. Future chlamydia control efforts will require a population-based approach focused on reengaging sexually active adults of diverse economic and migratory backgrounds. Funding: This was an unfunded study using routinely collected public health data.

Original languageEnglish (US)
Article number100143
JournalThe Lancet Regional Health - Western Pacific
StatePublished - Jun 2021

Bibliographical note

Funding Information:
MKS, CW, PZZ, and BY all had full access to the data. MKS, KMS, ER, CW, WWY, and PZZ were involved in study design, analysis of data, interpretation. All authors were involved in interpretation of the data and either drafting or revising the final report. This was an unfunded study using routinely collected public health data maintained by the Dermatology Hospital of the Southern Medical University. The datasets analyzed in this report are not publicly available because the data are owned by third parties. Permission to access these data can be requested through inquiries to the Dermatology Hospital of the Southern Medical University in China. Editor note: The Lancet Group takes a neutral position with respect to territorial claims in published maps and institutional affiliations.

Publisher Copyright:
© 2021


Dive into the research topics of 'Spatiotemporal analysis of 11 years of Chlamydia trachomatis data from southern China'. Together they form a unique fingerprint.

Cite this