Objectives The aim of this study was to determine the prevalence of Chlamydia trachomatis infection and other sexually transmitted infections (STI) in female sex workers (FSW) in Tunisia.

Methods 188 prostitutes from three Tunisian towns were enrolled at their weekly medical visit. Demographic and sexual behaviour data were collected. C trachomatis, Neisseria gonorrhoeae, herpes simplex virus 2 (HSV-2) and human papillomavirus (HPV) were detected by PCR. Blood samples were tested for the presence of HIV, hepatitis B core, hepatitis C virus (HCV), HSV-2, C trachomatis and syphilis antibodies and Hbs antigen.

Results The mean age of the FSW was 34 years. They had worked in the sex industry for 6.6 years on average. Nearly all FSW (98.9%) had at least one marker of STI. A current infection was found in 86.7% of cases. Only one STI was noted in 37.2% and two or more in 49.5% of FSW. C trachomatis, N gonorrhoeae, HPV and HSV-2 PCR were positive in 72.9%, 11.2%, 44.1% and 1.1% of cases, respectively. Syphilis, HCV antibodies and Hbs antigen were detected in poor percentages, 2.7%, 1.1% and 0.5% of cases, respectively. No case of HIV infection was noted. No epidemiological or clinical factors were associated with STI. Only disturbed bacterial vaginal flora was found to be associated with C trachomatis infection.

Conclusion In this study, a high rate of C trachomatis infection was observed. The detection of this microorganism should be introduced in systematic surveillance of Tunisian FSW.