Factors associated with HIV and syphilis infection among female sex workers in three cities in Papua New Guinea: findings from Kauntim mi tu, a biobehavioral survey

Background: In this paper, factors associated with HIV and syphilis infection in three cities in Papua New Guinea are explored. Methods: Respondent-driven sampling surveys among FSW in Port Moresby, Lae, and Mt. Hagen (2016-17) were conducted. FSW who were aged >= 12 years, who were born female, who spoke English or Tok Pisin and who had sold or exchanged vaginal sex in the past 6 months were eligible to participate. Participants were interviewed face-to-face and offered rapid HIV and syphilis testing. Survey logistic procedures were used to identify factors associated with HIV and syphilis infection, including modern contraception use, physical violence and having a casual male partner. Weighted data analysis was conducted. Results: Overall, 2901 FSW (Port Moresby, 673; Lae, 709; and Mt. Hagen, 709) were enrolled in the study. HIV prevalence was 15.2% in Port Moresby, 11.9% in Lae and 19.6% in Mt. Hagen. Factors associated with HIV varied by city; for example, use of modern contraception in Port Moresby, experiences of physical violence in Lae and ever having tested for HIV in Mt. Hagen. No one variable was associated with HIV in all cities. Prevalence of syphilis infection was 7.1%, 7.0%, and 3.0% in Port Moresby, Lae, and Mt. Hagen, respectively. Factors associated with syphilis infection also varied by city and were only significant in Lae. Conclusion: The different factors associated with HIV and syphilis infection in each city highlight the complex HIV and syphilis epidemics among FSW and the importance of conducting surveys in multiple locations and developing local interventions.