Key mechanisms for chlamydia control in Guangdong, China: a mixed-methods causal-loop analysis

The incidence of Chlamydia trachomatis (C. trachomatis) infections is increasing globally, with approximately 131 million new cases annually, leading to significant reproductive health complications. Evidence on the impact of chlamydia prevention and treatment programs in developing countries is scarce, leaving a critical gap in implementation. This study, conducted in Guangdong Province, China, aims to identify leverage points to facilitate evidence implementation by visualizing key factors and their interrelationships influencing chlamydia control through a causal loop diagram (CLD).

In this mixed-methods study, variables were systematically identified through literature review (n = 15 studies), forming an initial conceptual model. Qualitative interviews with 70 stakeholders across five cities revealed implementation barriers and facilitators, refining the model. Second, a semi-quantitative MICMAC (Impact Matrix Cross-reference Multiplication Applied to Classification) analysis was employed to calculate link density and ranked influence-dependence measures.

The initial CLD consists of a main framework and four subsystems-Center for Public Health (CPH), Hospital, Target Audience, and the Government-comprising a total of 47 variables. A thematic analysis of the interview data revealed four major themes: health education, policy support, accurate identification of high-risk populations, and adherence. Two central feedback loops capture the core mechanisms. The first is a balancing loop involving policy requirements, community mobilization, and health education coverage and influencing variables such as condom promotion, infection rates, and disease burden. The second is a reinforcing loop driven by the public's awareness of chlamydia prevention and control, amplifying the effects of educational outreach and stigma reduction efforts. Triangulation revealed alignment in health education centrality.

These findings inform the development of context-specific interventions for chlamydia control in resource-limited settings. Health education, supported by policy and community engagement, may represent a central intervention. Targeted actions, such as expanding premarital and prenatal consultations and youth outreach in remote areas, could help reduce transmission through addressing stigma and other social barriers to care. Future system dynamics modeling is recommended to evaluate the long-term economic impact of chlamydia control and guide sustainable policy investment.

Not applicable.