HIV Vulnerability and Oral PrEP Use Among Injecting Drug Users in Nairobi

Overview

This cross-sectional study assessed HIV risk and oral PrEP awareness and use among HIV-negative people who inject drugs (PWID) in Nairobi. Despite high HIV vulnerability, PrEP knowledge and uptake remain low in this population, highlighting critical gaps in prevention efforts.

Background

Globally, PWID face a substantially elevated risk of HIV infection, estimated to be 22 to 24 times higher than the general population. In Kenya, HIV prevalence among PWID was 18.7% in 2021, with key populations disproportionately affected. Oral PrEP has proven efficacy in reducing HIV acquisition from both sexual and injection exposures, yet awareness and use among PWID in Kenya remain limited due to multiple barriers including stigma, provider hesitancy, and socioeconomic challenges. This study aimed to characterize HIV risk, PrEP knowledge, and use among PWID in Nairobi to inform targeted interventions.

Data Highlights

A total of 264 HIV-negative PWID were recruited from four drop-in centers in Nairobi. Sample size was calculated to detect meaningful differences in PrEP uptake with 95% power, accounting for 14% loss to follow-up. Recruitment was stratified by gender and age, using convenience sampling through peer educators. The study population reflects a key demographic at high risk for HIV acquisition but with limited PrEP awareness and use.

Key Findings

• PWID in Nairobi have a high HIV prevalence estimated at 18.7%, significantly exceeding the national adult prevalence of 3.1%.
• Oral PrEP reduces HIV risk by 99% from sexual exposure and 74% from injection drug use, yet uptake among PWID remains low.
• More than half of PWID surveyed had never heard of PrEP, and misconceptions about its use were common among those aware.
• Barriers to PrEP use include stigma, socioeconomic factors such as homelessness and cost, limited healthcare provider engagement, and lack of targeted outreach to PWID.
• Provider hesitancy to prescribe PrEP to PWID and inadequate research on tailored interventions contribute to low PrEP utilization.
• Effective PrEP promotion among PWID requires addressing knowledge gaps, improving healthcare access, and reducing stigma within this population.

Clinical Implications

Healthcare providers should proactively engage PWID in discussions about PrEP and address misconceptions to improve uptake. Tailored interventions that consider the unique socioeconomic and behavioral challenges faced by PWID are essential. Expanding targeted outreach and integrating PrEP services within addiction treatment and harm reduction programs can enhance prevention efforts in this high-risk group.

Conclusion

PWID in Nairobi remain a key population with elevated HIV risk but low awareness and use of oral PrEP. Addressing barriers to PrEP uptake through targeted education, provider training, and integrated service delivery is critical to reducing HIV transmission in this vulnerable group.

References

1. NASCOP Kenya 2021 -- HIV Prevalence and Key Populations
2. Bangkok Tenofovir Study 2013 -- PrEP Efficacy Among PWID
3. Kenya Ministry of Health 2017 -- National PrEP Guidelines
4. SAPTA Kenya -- Support for Addictions Prevention and Treatment in Africa