Chlamydia trachomatis (CT) is the most common sexually transmitted bacterial infection globally, significantly affecting adolescent girls and young women (AGYW) in South Africa. This study investigated CT prevalence and genotypic diversity among 298 AGYW from Cape Town and Johannesburg, revealing an overall prevalence of 29.5%. Prevalence was higher in Cape Town (41.6%) compared to Johannesburg (17.4%; p<0.0001). Genetic analysis identified 34 sequence types, including 15 novel variants. Longitudinal data highlighted frequent reinfections or persistent infections despite treatment. These findings underscore the importance of addressing CTs genetic diversity for improved reproductive health strategies and vaccine development.

The authors have declared no competing interest.

This work was supported by the EDCTP Strategic Primer grant (SP.2011.41304.038; PI: J. Passmore, UCT) and a self-initiated grant from the South African Medical Research Council (PI: J. Passmore, UCT).

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Ethics committees of the University of Cape Town and Witwatersrand University gave ethical approval for this work (#267/2013 and #M130745, respectively).

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All data produced in the present study are available upon reasonable request to the authors