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Estimating the Number of People Who Inject Drugs, Female Sex Workers, and Men Who Have Sex with Men, Unguja Island, Zanzibar: Results and Synthesis of Multiple Methods

AIDS and Behavior volume 18, pages 25–31 (2014)Cite this article

Abstract

To determine the number of people who inject drugs (PWID), female sex workers (FSW) and men who have sex with men (MSM) living in Unguja Island, Zanzibar in 2011/2012, we applied several, practical population size estimation methods including literature review, unique object multiplier, recapture from the 2007 survey, wisdom of the crowds and service multiplier. We synthesized findings and presented them to a panel of experts in order to determine plausible estimates for each population. The estimates adopted by a panel of experts as being most plausible were 3,000 for PWID, 3,958 for FSW and 2,157 for MSM. We learned that no one method could be concluded to be the standard for all three populations. The estimates we found, though still not perfect, are useful for the HIV programmes serving these populations.

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Acknowledgments

We are grateful to the University of California, San Francisco and the US Centers for Disease Control and Prevention, Tanzania and Atlanta, for the esteemed technical support. Special thanks go to the study participants, the study staff, the peer educators, the Ministry of Health and all the organizations working with key populations in Zanzibar for their contribution to the planning and implementation of this study. This study was supported by the Global Fund against AIDS, Tuberculosis and Malaria Round 6 through Grant number ZAN-607-G05-H and two Cooperative Agreements with US Centers for Disease Control and Prevention #5UGPS002039-02 and #5UGPS001472-03. The findings and conclusions in this paper are those of the authors and do not necessarily represent those of the US Centers for Disease Control and Prevention.

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Affiliations

  1. Zanzibar AIDS Control Program, Ministry of Health, P.O. Box 1300, Zanzibar, Tanzania

    Farhat J. Khalid, Fatma M. Hamad, Asha A. Othman, Ahmed M. Khatib, Sophia Mohamed & Ameir Kh. Ali

  2. Directorate of Preventive Services and Health Education, Ministry of Health, Zanzibar, Tanzania

    Mohammed J. U. Dahoma

Authors
  1. Farhat J. Khalid
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  2. Fatma M. Hamad
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  3. Asha A. Othman
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  4. Ahmed M. Khatib
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  5. Sophia Mohamed
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  6. Ameir Kh. Ali
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  7. Mohammed J. U. Dahoma
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Correspondence to Farhat J. Khalid.

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Khalid, F.J., Hamad, F.M., Othman, A.A. et al. Estimating the Number of People Who Inject Drugs, Female Sex Workers, and Men Who Have Sex with Men, Unguja Island, Zanzibar: Results and Synthesis of Multiple Methods. AIDS Behav 18, 25–31 (2014). https://doi.org/10.1007/s10461-013-0517-x

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Keywords

  • Female sex workers
  • Men who have sex with men
  • People who inject drugs
  • Tanzania
  • Population size