amfAR, The Foundation for AIDS Research

New Study Investigates PrEP for Female Sex Workers in Thailand

By Jennifer Sherwood, Public Policy Office, amfAR

new study 
From left: Surang Janyam, Jennifer Sherwood (amfAR Public Policy Office), Dr. Dusita Phuengsamran, Chamrong Phaengnongyang (SWING Foundation), Dr. Michele Decker

New amfAR-supported research, coordinated by amfAR’s Public Policy Office and led by principal investigator Dr. Dusita Phuengsamran of the Institute for Population and Social Research (IPSR) at Mahidol University, Bangkok, Thailand, kicked off in May. The mixed methods study will assess combination HIV prevention needs, including pre-exposure prophylaxis (PrEP), among female sex workers in Bangkok and Pattaya, Thailand.

The study team brings together diverse expertise from the Service Workers in Group (SWING) Foundation, a Thai advocacy organization for sex workers; IPSR; Johns Hopkins Bloomberg School of Public Health (JHSPH) in Baltimore, Maryland; and amfAR. The researchers will collect data using focus groups, key informant interviews, and a questionnaire among 180 female sex workers to examine PrEP knowledge and acceptability and to document behavioral, social, and structural factors known to place women at risk for HIV.

Despite indications that in Bangkok about 2.5% of venue-based female sex workers are living with HIV, it is estimated that the prevalence of HIV infection among freelance or street-based female sex workers is between 20% and 45%.1,2 These numbers demonstrate a clear unmet need for HIV prevention among these higher-risk groups.

“It is well recognized that the high HIV risk among female sex workers often stems from sources beyond their immediate control, including discrimination, violence at the hands of police and clients, and coercive condom negotiation that undermines their ability to mitigate risk,” said study investigator Dr. Michele Decker of JHSPH. “In recognition of these circumstances, oral PrEP may offer significant promise for them as a biomedical means for HIV prevention.” 

kromFrom left: Khomkrit Tapienthong (IPSR), Dr. Dusita Phuengsamran, Jennifer Sherwood, Leah Koenig (JHSPH)However, gaps in data on the acceptability and feasibility of offering PrEP as an HIV prevention option for female sex workers in Thailand have made it more challenging to effectively advocate to expand PrEP access to them. In the past five years, clinical trials have demonstrated the effectiveness of PrEP in preventing HIV acquisition, but have also exposed several issues related to real-world effectiveness, including adherence among female participants. New research is required to understand barriers to adherence, acceptability of PrEP, optimal delivery methods, and feasibility of PrEP implementation. The researchers plan to tackle these questions in order to inform strategies for incorporating this new tool into a comprehensive HIV prevention package for Thai women.

“This project is of particular importance because it will yield the first piece of information about PrEP for female sex workers, which is crucial for advocacy efforts to make it available to them,” said investigator Surang Janyam, director of the SWING Foundation. “I and the sex workers community hope that this project will be followed by others to ensure that female sex workers have access to PrEP when necessary.”

Close collaboration with SWING and the sex work community on study design, implementation, and dissemination will help to maximize its benefit and relevance, both in terms of guiding future PrEP roll-out and other elements of combination prevention. Results will be disseminated at a community consultation scheduled to take place in October 2016.

“Engaging SWING and the sex worker community throughout the study is very important and will increase the reliability and use of the findings. We are looking forward to the changes we can make,” said Dr. Phuengsamran.

amfAR has released a fact sheet on this study, PrEP Acceptability Among Female Sex Workers in Thailand


1 Nhurod P, Bollen LJ, Smutraprapoot P, et al. Access to HIV testing for sex workers in Bangkok, Thailand: a high prevalence of HIV among street-based sex workers. The Southeast Asian Journal of Tropical Medicine and Public Health. Jan 2010;41(1):153-162.

2 Manopaiboon C, Prybylski D, Subhachaturas W, et al. Unexpectedly high HIV prevalence among female sex workers in Bangkok, Thailand in a respondent-driven sampling survey. International Journal of STD & AIDS. Jan 2013;24(1):34-38.