The Hidden Burden of Extragenital Chlamydial and Gonorrheal Infections in a Population of U.S. Army Service Members and Their Medical Beneficiaries

Introduction Sexually transmitted infections (STIs) place a high burden on the Military Health System (MHS) and adversely impact service members' ability to perform their duties. This study examined Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) epidemiology among a population of U.S. service members and their beneficiaries and explored differences in CT and NG prevalence by anatomic site and sex. Methods We conducted cross-sectional analyses of enrollment visit data from participants in a randomized controlled trial of a behavioral intervention to prevent STIs (Knocking out Infections through Safer sex and Screening) at Joint Base Lewis-McChord, WA and Fort Liberty, NC. At enrollment, participants completed questionnaires and provided biological specimens for nucleic acid amplification testing for CT and NG. Results Among 439 participants enrolled between November 2020 and February 2023, 423 (96.4%) were on active duty in the U.S. Army. Of these participants, 173 (39.4%) were female and the median age was 23 (interquartile range 21, 25) years. A reactive test for CT or NG at any anatomic site was observed in 120 participants (prevalence 27.3%), including 60 who had a reactive test for CT or NG at oropharyngeal and/or anorectal sites (prevalence 13.7%). Anorectal CT prevalence was significantly higher among females than males (12.7% vs. 5.3%; P =. 005). Conclusions This study highlights opportunities to improve screening to identify cases of CT and/or NG that may otherwise go undetected and thus lead to adverse health outcomes, especially for females. The high burden of extragenital CT/NG also underscores the importance of generating evidence to inform more comprehensive screening, treatment, and prevention strategies.