Background As a concentrated epidemic, HIV is spreading rapidly in one or more sub-groups, but in the general population its prevalence is relatively low. Female sex workers (FSWs) and their partners are at greater risk for HIV infection. A successful comprehensive HIV surveillance should include the prevalence of HIV, sexually transmitted infections (STIs) and associated risk behaviours. The aim of the present study was to determine the prevalence of HIV and STIs including gonorrhoea, Chlamydia, Herpes simplex type 2 (HSV-2) and syphilis among FSWs in order to plan appropriate interventions.

Materials This is a cross-sectional study of 278 FSWs conducted in Shiraz, by using respondent driven sampling (RDS), from June to March 2010. The recruitment chain started with 14 seeds, were taken for HIV, syphilis, HSV-2, gonorrhoea, and Chlamydia tests.

Results The HIV prevalence was 4.7% (13/278); the most prevalent STI was HSV-2 9.7% (27/278), followed by Chlamydia 9% (25/278), gonorrhoea 1.43% (4/278) and syphilis (0/278). The FSWs reported history of drug abuse (69.9%) of which 16.4% had history of injecting drug use (IDU). 79.8% of the participants stated, their incentive for having sex in the previous month was financial. During this period, 24.4% had unprotected intercourse in previous month and 30.1% used condom sometimes, 4.7% almost every time and 40.6% every time.

Conclusions The necessity of implementing preventative intervention programme is an urgent issue. Educational programmes on mode of transmission of HIV/STIs, STIs syndrome, and HIV/STIs counselling, testing and reproductive healthcare should be included in FSWs- oriented programmes.