Introduction HIV Biological and Behavioural Surveillance surveys (BBSS) were conducted among female sex workers (FSW) in Armenia in 2010, 2012, and 2014. These surveys used respondent driven sampling (RDS), an effective method for recruiting hidden populations.

Methods In 2016 the BBSS using RDS among FSW were conducted in Yerevan the capital of Armenia. The sample size was 300. Prevalence of HIV, syphilis, Trichomoniasis, Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) were measured and knowledge and sexual risk behaviours were assessed.

Results HIV prevalence was low at 0.1% among FSW in Yerevan. NG prevalence was 4%, 29% of FSW were positive for Trichomoniasis. The prevalence of CT was 12%, syphilis prevalence was 4%. 34% of FSW in Yerevan reported having had genital ulcers or sores in the past 12 months.

More than 95% of FSW in all survey locations reported using condoms the last time they had sexual intercourse with a client. 89% of FSW in Yerevan reported sex with non-commercial partners in the past 12 months and 38% reported not using condoms during their last sex with them.

Conclusion There was a significant increase from 90.2% in 2012 to 99.6% in 2016 in the use of condoms with the most recent client among FSW. But there was no overall significant change in STI prevalence among FSW between 2012 and 2016. Many FSW reported having sex with non-commercial partner, and condom use with them is significantly lower than with clients. Therefore, we can conclude that unprotected sex with non-commercial partners is the main risk factor to get STI for FSW in Armenia. These findings highlight the need for HIV prevention interventions that engage both FSW and their sex partners, especially non-commercial. Improvement of condom negotiation skills, provision of HIV/AIDS risk and transmission education should be the focus of interventions targeting FSW. Additionally, health care and other service providers should encourage routine HIV testing and STI screening for FSW and their partners.