Co-infection with genital gonorrhoea and genital chlamydia in female sex workers in Yunnan, China

An observational study on prevalence of co-infection with gonorrhoea and chlamydia was conducted among female sex workers (FSWs) in Kunming, China. A total of 505 FSWs participated in the study. All eligible participants gave informed consent. Demographic, behavioural and clinical information of the participants was gathered by direct structured interviews. Tampon swabs were collected to test for Chlamydia trachomatis and Nesseria gonorrhoeae. One-hundred and twenty-four (24.6%) FSWs were co-infected with these two pathogens. Of the 191 FSWs with gonorrhea, 124 (64.9%, 95% confidence interval [CI] = 57.9–71.3%) were co-infected with chlamydia which was significantly higher than the proportion (41.9%, 95% CI = 36.4–47.6%) co-infected with gonorrhoea among 296 FSWs with chlamydia ( P < 0.001). Only 47 of 191 (24.6%) FSWs with gonococcal infection and 28 of 124 (22.6%) with co-infection with gonorrhoea and chlamydia reported vaginal discharge. The results of the study justify the recommendation in the national sexually transmitted disease (STD) guidelines that patients infected with gonorrhoea also be treated routinely with an anti-chlamydial regimen. However, a periodic mass treatment may be considered in some circumstances in STD control programmes to rapidly reduce the infections in this population.