Research article Prevalence and behavioural risks for HIV and HCV infections

Objectives: Data on the extent of drug use and associated HIV, hepatitis C and hepatitis B infection in West Africa are lacking. The objectives of ANRS12244 UDSEN study were to estimate the size of the heroin and/or cocaine drug user (DU) population living in the Dakar area (Senegal), and assess the prevalence and risk factors of HIV, hepatitis C virus (HCV) and hepatitis B virus (HBV), including behavioural determinants in this population, in order to set up an integrated prevention and treatment programme for DUs. Design and methods: A capture-recapture method was applied for population size estimation, whereas the respondent-driven sampling (RDS) method was used to recruit a sample of DUs living in the Dakar area and determine HIV, HBV and HCV prevalence. Behavioural data were gathered during face-to-face interviews, and blood samples were collected on dried blood spots for analysis in a central laboratory. Data analysis was performed using the RDS analysis tool, and risk factors were determined by logistic regression. Access to laboratory results was organized for the participants. Results: The size of the DU population in the Dakar area was estimated to reach 1324 (95 % confidence interval (95 % CI: 12811367)). Based on the 506 DUs included in the study, the HIV, HCV and HBV prevalence were 5.2 % (95 % CI: 3.86.3), 23.3% (95 % CI: 21.225.2) and 7.9 % (95 % CI: 5.211.1), respectively. In people who inject drugs (PWID), prevalence levels increased to 9.4 % for HIV and 38.9 % for HCV (p0.001 when compared to those who never injected). Women were more at risk o