Introduction People who inject drugs (PWID) in Sub-Saharan Africa have limited access to comprehensive HIV services. While it is important to inform programming, knowledge about factors influencing access to comprehensive HIV services is scarce. We assessed the proportions of PWID with access to HIV prevention services and associated socio-cognitive factors in Tanzania.

Methods A cross-sectional survey was conducted among PWID between October and December 2017 in Dar es Salaam, Tanzania. Data on access to HIV prevention services, demographics and selected socio-cognitive factors were collected through structured face-to-face interviews. Weighted descriptive and forward selection multivariable logistics regression analyses were done to assess independent associations between HIV prevention services and predictors of interest. The results were two tailed and a p-value of less than 0.05 was considered statistically significant.

Results The study included 611 PWID (males: 94.4%) with a median age of 34 years (Interquartile Range (IQR), 29-38). A large majority of participants reported to have access to condoms (87.8%), sterile needles/syringes (72.8%) and ever tested for HIV (66.0%). About half (52.0%) reported to have used condoms in the past one month and about a third (28.5%) accessed a peer educator. The odds of testing for HIV decreased among participants who perceived their HIV risk to be high (aOR = 0.29; 95%CI: 0.17-0.49) and those experienced sexual violence (aOR = 0.60; 95%CI 0.37-0.98). However, the odds of testing for HIV increased among participants with secondary level of education (aOR = 2.16; 95%CI: 1.06-5.55), and those who reported having correct comprehensive HIV knowledge (CCHK) (aOR = 1.63; 95%CI 1.12-2.41). The odds of access to condoms increased among females (aOR = 2.23; 95%CI: 1.04-5.02) but decreased among participants with secondary level of education (aOR = 0.41; 95%CI: 0.19-0.84), an income of >TZS 200,000 (aOR = 0.39; 95%CI: 0.23-0.66) and those who perceived their HIV risk to be high (aOR = 0.13; 95%CI: 0.03-0.36). The odds of access to peer educators was higher among participants with primary (aOR = 1.61; 95%CI: 1.01-2.26), and secondary (aOR = 2.71; 95%CI: 1.39-5.33) levels of education. The odds of access to sterile needle and syringe decreased among participants who perceived their HIV risk to be high (aOR = 0.11;95%CI 0.05-0.22), and low-medium (aOR = 0.25;95%CI 0.11-0.52) but increased among those with primary level of education (aOR = 1.72;95%CI 1.06-2.78).

Conclusion Access to condom, HIV testing, sterile needles and syringes were relatively high among PWID. However, condom use and access to peer educators was relatively low. HIV knowledge and risk perception, gender, education, and sexual violence influenced access to HIV prevention services. There is an urgent need to address the identified socio-cognitive factors and scale up all aspects of HIV prevention services to fast-track attainment of the 2025 UNAIDS goals and ending the HIV epidemic.