Prevalence and predictors of asymptomatic Chlamydia trachomatis and Neisseria gonorrhoeae in a Ugandan population most at risk of HIV transmission

The aim of this study was to establish the prevalence of asymptomatic Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) in key populations at increased risk of transmission of HIV. Additionally, we aimed to identify the associated risk factors for asymptomatic sexually transmitted infections (STIs) and evaluate the acceptability of self-collected samples. Asymptomatic people living with HIV (PLHIV) in the following categories were offered testing: discordant couples, young adults, pregnant patients and those attending the 'most-at-risk-population' clinic. Patients provided first-pass urine, self-collected vaginal swabs or both to test for NG and CT by polymerase chain reaction using BD ProbeTec™. Patients also completed an acceptability questionnaire, including the negative partner of an HIV-positive participant. Three hundred and sixty-three PLHIV had an STI screen. Asymptomatic STIs were only diagnosed in women (prevalence 5.7%), overall prevalence 3.9% (n = 14). Factors independently associated with an STI in women were being under 25 years (OR 9.63 95% CI 1.56-59.5) and having more than one sexual partner (OR 8.06 95% CI 1.07-60.6). Four hundred and seven completed the acceptability questionnaire. More than 95% of patients found self-sampling easy and comfortable and 83.8% would believe the results. Women significantly preferred the option of self-sampling, 56.9% versus 29.3% of men (p < 0.001). Acceptability of self-sampling was high. Young women with or at risk of HIV are an important target for STI testing regardless of symptoms. There is need for diagnostic tests that are inexpensive, rapid and accurate especially in resource-limited settings.