[Show abstract][Hide abstract] ABSTRACT: People who inject drugs (PWID) are at higher risk of acquiring HIV due to risky injection and sexual practices. We measured HIV prevalence and behaviors related to acquisition and transmission risk at two time points (2007 and 2012) in Zanzibar, Tanzania. We conducted two rounds of behavioral and biological surveillance among PWID using respondent-driven sampling, recruiting 499 and 408 PWID, respectively. Through faceto- face interviews, we collected information on demographics as well as sexual and injection practices.
We obtained blood samples for biological testing. We analyzed data using RDSAT and exported weights into STATA for multivariate analysis. HIV prevalence among sampled PWID in Zanzibar was 16.0 % in 2007 and 11.3 % in 2012; 73.2 % had injected drugs for 7 years or more in 2007, while in the 2012 sample this proportion was 36.9 %. In 2007, 53.6 % reported having shared a needle in the past month, while in the 2012 sample, 29.1 % reported having done so. While 13.3 % of PWID in 2007 reported having been tested for HIV infection and received results in the past year, this proportion was 38.0 % in 2012. Duration of injection drug use for 5 years or more was associated with higher odds of HIV infection in both samples. HIV prevalence and indicators of risk and preventive behaviors among PWID in Zanzibar were generally more favorable in 2012 compared to 2007—a period marked by the scale-up of prevention programs focusing on PWID. While encouraging, causal interpretation needs to be cautious and consider possible sample differences in these two cross-sectional surveys. HIV prevalence and related risk behaviors persist at levels warranting sustained and enhanced efforts of primary prevention and harm reduction.
Full-text · Article · Nov 2014 · AIDS and Behavior
[Show abstract][Hide abstract] 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.
No preview · Article · May 2013 · AIDS and Behavior
[Show abstract][Hide abstract] ABSTRACT: Men who have sex with men and inject drugs (MSM-IDU) are particularly vulnerable to HIV infection and have the potential to transmit HIV across multiple populations through their male and female sexual partners and injection drug-using partners.
Respondent-driven sampling was used to recruit men who reported engaging in anal sex with another man in the past 3 months, aged ≥15 years, and living in Unguja, Zanzibar. Participants responded to a face-to-face interview about their HIV and injecting risk behaviours and were tested for HIV, Hepatitis B (HBV) and C (HCV) and syphilis.
Among the 509 MSM who enrolled in the survey, 14% (n=66) reported injecting drugs in the past 3 months among which 66% used heroin, 60% used a needle after someone else had and 68% passed a needle to someone else after using it. MSM-IDU were significantly more likely to have two or more non-paying male receptive sex partners and to have engaged in group sex in the past month, to have symptoms of a sexually transmitted infection in past 6 months, to have been arrested or beaten in the past 12 months and to be infected with HIV and co-infected with HIV and HCV compared to MSM who did not inject drugs. MSM-IDU were less likely to have used a condom at last sex with a non-paid female partner, to know where to get a confidential HIV test and to have ever been tested for HIV compared to MSM who did not inject drugs.
MSM-IDU, and MSM in general, in Unguja practice multiple high-risk behaviours that put them at risk for blood-borne and sexual transmission of HIV and HCV infection. Targeted interventions for MSM-IDU must account for the overlap of high-risk sexual and drug-using networks and integrate injection drug use and HIV services.
Full-text · Article · Nov 2010 · The International journal on drug policy
[Show abstract][Hide abstract] ABSTRACT: We conducted a respondent driven sampling survey to estimate HIV prevalence and risk behavior among men who have sex with men (MSM) in Unguja, Zanzibar. Men aged ≥ 15 years living in Unguja and reporting anal sex with another man in the past 3 months were asked to complete a questionnaire and provide specimens for biologic testing. HIV prevalence was 12.3% (95% confidence interval 8.7, 16.3). HIV infection was associated with injecting drugs in the past 3 months, Hepatitis C virus infection and being paid for sex in the past year. Interventions for MSM in Zanzibar are needed and should include linkages to prevention, care and treatment services.
Full-text · Article · Dec 2009 · AIDS and Behavior