Background
Kenyan guidelines recommend syndromic management for sexually transmitted infections (STIs) among people living with HIV at urogenital anatomical sites. However, STIs like Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) can cause morbidity and can be transmitted even without symptoms at multiple anatomical sites. We assessed the prevalence of CT and NG using universal nucleic acid amplification test (NAAT)-based testing among adults in Western Kenya.
Methods
From December 2021 to May 2023, we enrolled participants living without HIV in Kericho and Homa Bay, Kenya, who were aged 14-55 years and reported a recent history of an STI, transactional sex, condomless sex, and/or injection drug use. Participants provided urine, oropharyngeal swabs, and anorectal swabs for NAAT for NG and CT (GeneXpert®, Cepheid). Multivariable robust Poisson regression models were used to estimate prevalence ratios (PRs) and 95% confidence intervals (CIs) for factors potentially associated with the prevalence of both STIs combined.
Results
Upon enrollment, STI tests were performed on 405 participants, including 323 (79.8%) assigned female sex at birth and 324 (80.0%) aged 24 years or younger. A total 43 (10.6%) had a history of any STI diagnosed in the 24 weeks prior to enrollment. Inconsistent condom use was reported by 309 (76.3%) participants and 201 (49.6%) had ≥10 new sexual partners in the previous 12 weeks. NAAT identified an STI in 143 (35.3%) participants, with 111 (27.4%) CT and 76 (18.8%) NG diagnoses. CT/NG diagnoses were reported at a single anatomical site in 37 (9.1%) participants and multiple anatomical sites in 104 (25.7%) participants. Among 117 participants with an anorectal STI, 16 (13.7%) reported receptive anal sex and 3 (18.8%) participants did not report a urogenital STI. Females had higher prevalences of urogenital (33.7% vs. 18.3%, p=0.01) and anorectal STIs (31.9% vs. 17.1%, p=0.01). Prevalent STIs were reported in 19 (13.3%) participants at oropharyngeal and/or anorectal sites that were not detected at urogenital sites. In multivariable analyses, there were no statistically significant associations between sociodemographic variables and STI prevalence.
Conclusions
A high prevalence of urogenital and anorectal STIs were identified in a Western Kenyan community, particularly among females. Implementing universal NAAT-based anorectal STI screening of sexually active adolescents and young adults could reduce STI burden in this population.