Risk behaviour, healthcare access and prevalence of infection with Chlamydia trachomatis and Neisseria gonorrhoeae in a population-based sample of adults in Barbados

Objectives: To estimate the prevalence of urogenital infection with Chlamydia trachomatis and Neisseria gonorrhoeae in people 18 to 35 years of age in Barbados, and to examine factors associated with infection. Methods: Cross-sectional survey of randomly selected people from the voters' register of one electoral district and the collection of urine samples for testing by PCR. Results: The response rate was 82%; 408 people (195 males and 213 females) completed a questionnaire and had their urine collected. 397 urine samples were satisfactorily tested. Prevalence of C trachomatis urogenital infection was 11.3% (95% CI +/- 2.9) and N gonorrhoeae 1.8% (95% CI +/- 1.2) with 12.6% (95% CI +/- 3.1) having either or both infections. The difference in prevalence by gender was not significant. Multivariate logistic regression showed that prevalence of C trachomatis and/or N gonorrhoeae decreased with increasing age (per year OR 0.89, 95% CI 0.84 to 0.96, p=0.001), and decreasing time (<= 6 months vs >6 months) since last medical consultation (OR 0.44, 95% CI 0.22 to 0.88, p=0.02). Most (76%) infected people were asymptomatic. Condom use at last intercourse with a partner not being lived with was not protective (reported by 52%, p=0.617). The usual source of health care was evenly distributed between the public and private sectors and was not associated with infection. Only 30% of people had ever heard of chlamydia, whereas 92% were aware of gonorrhoea. Conclusions: Asymptomatic infection with C trachomatis is an important reservoir of infection, which will remain undetected unless physicians and young people are made aware of this and screening is introduced.