Chlamydia Prevalence and Associated Behaviours Among Female Sex Workers in Vanuatu: Results from an Integrated Bio-behavioural Survey, 2011


There is insufficient data on sexually transmitted infections (STI) and related behaviours among key populations, including female sex workers (FSW), in the Pacific region. Using respondent driven sampling, we conducted an integrated bio-behavioural survey with FSW in Vanuatu (aged ≥18 years) to investigate risk behaviours associations with Chlamydia trachomatis (CT). Weighted population estimates and correlates of CT infection were calculated. Among 149 FSW, prevalence of CT was 36 % (95 % CI 26–48 %). Few FSW reported consistent condom use with recent transactional sex partners (TSP) (8 %; 95 % CI 2–13 %). CT infection was positively associated with increasing number of TSP (adjusted odds ratio [AOR] 1.1; 95 % CI 1.0–1.2) and group sex (AOR 2.9; 95 % CI 1.1–8.2). CT was negatively associated with increasing age of first sex (AOR 0.6; 95 % CI 0.5–0.9) and previous STI treatment (AOR 0.1; 95 % CI 0.0–0.4). A comprehensive public health strategy for prevention and treatment of STI among FSW, incorporating community empowerment strategies, FSW-targeted health services and periodic presumptive treatment, is urgently needed in Vanuatu.

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We wish to thank the Vanuatu Ministry of Health for their ongoing support and for laboratory testing; NRL (Melbourne, Australia) for laboratory testing; Wan Smolbag for coordinating data collection and entry and management of the field researchers; WHO Western Pacific Regional Office and the Pacific UNAIDS Coordinator for their technical support in project implementation. Caroline van Gemert received a Travel Grant from the Ian Potter Foundation to receive training in Respondent Driven Sampling from Lisa G Johnston of Tulane University and University of California, San Francisco in USA. We thank the Pacific Island HIV and STI Response Fund Grant, a collaborative funding mechanism by the Australia and New Zealand governments and managed by the Secretariat of the Pacific Community for funding this project. Laboratory testing of specimens at the Port Vila Central Hospital was provided by the Global Fund Round 7 Grant through the Vanuatu Ministry of Health. Finally, we thank all participants of the study for their valuable input.

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Correspondence to Caroline van Gemert.

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van Gemert, C., Stoove, M., Kwarteng, T. et al. Chlamydia Prevalence and Associated Behaviours Among Female Sex Workers in Vanuatu: Results from an Integrated Bio-behavioural Survey, 2011. AIDS Behav 18, 2040–2049 (2014).

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  • Integrated bio-behavioural survey
  • Female sex workers
  • Chlamydia
  • Pacific
  • Risk behaviours