Predictors of Knowledge and Risk Perception on Hepatitis B Virus Infection Among People Who Inject Drugs in Dodoma, Tanzania: A Cross-sectional Study

Abstract

Background: Globally, an estimated 15.6 million individuals inject drugs, with about 1.4 million living with HBV infection. People who inject drugs (PWIDs) represent one of the populations most vulnerable to hepatitis B virus (HBV) infection due to frequent exposure to contaminated injecting equipment and limited access to preventive and treatment services. Despite this high vulnerability, a substantial gap persists in knowledge and risk perception regarding HBV infection transmission and prevention among PWIDs. This study aimed to assess the predictors of knowledge and risk perception toward HBV infection among PWIDs.
Methods: A facility-based analytical cross-sectional study was conducted from June to September 2021 at the Itega Methadone Clinic in Dodoma, Tanzania. A total of 206 participants were selected through simple random sampling. Data were collected using a structured questionnaire assessing knowledge and risk perception toward hepatitis B virus infection. Binary logistic regression analysis was performed to identify predictors of poor knowledge and low risk perception, with statistical significance set at p <.05 and 95% confidence intervals (CI).
Results: Overall, knowledge about hepatitis B virus (HBV) transmission and prevention among people who inject drugs (PWIDs) was poor, with only 36% demonstrating adequate knowledge. Inadequate knowledge was significantly associated with low education level (AOR 2.44; 95% CI, 1.29–4.68; p=.005), short duration of methadone treatment (<1 year) (AOR 2.26; 95% CI , 1.12–4.55; p=.023), and low economic status (≤ TZS 100,000) (AOR 3.93; 95% CI, 1.01–15.25; p=.048). Regarding risk perception, the majority of participants underestimated their susceptibility to HBV infection, with only 25% perceiving themselves at high risk. Low risk perception was strongly predicted by low education level (AOR 12.68; 95% CI, 3.44–46.83; p˂.001) and inadequate knowledge (AOR 2.63; 95% CI, 1.28–5.39; p=.008).
Conclusion: This study revealed that knowledge and risk perception on hepatitis B virus infection among PWIDs remain alarmingly low. Only one-third of participants demonstrated adequate knowledge, and merely a quarter perceived themselves at high risk of infection. Low education level, economic disadvantage, and shorter duration of methadone treatment were the strongest predictors of poor HBV knowledge, while low risk perception was significantly associated with both low education and poor knowledge. These findings underscore the urgent need to integrate comprehensive HBV education, counselling, and vaccination awareness into harm-reduction and methadone programs. Interventions should particularly target newly enrolled clients and those with limited formal education or low income to foster accurate risk perception and improve preventive behaviours.