Immediate vs. delayed availability of free hepatitis B virus vaccine in a NYC research setting

The prevalence of hepatitis B virus (HBV) remains high among substance users despite availability of a safe vaccine. The New York Academy of Medicine conducts research at a storefront and mobile van. Study participants with a history of substance use were offered free HBV vaccine. Medical personnel administered vaccines three days a week at the storefront and one and a half days a week on the van (immediate). On alternate days, HBV vaccine was administered at a subsequent visit (delayed). Sociodemographics, sexual behavior, drug use, and knowledge of HBV and HBV vaccine were collected through interviewer-administered questionnaires. Characteristics associated with immediate vs. delayed HBV vaccination were assessed using chi-square and logistic regression. Of 282 enrollees, 67.9% were male, 48.6% Black, and 35.9% Latino; 30.5% were over 45 years of age, 42.5% have less than a 12th grade education, 74.1% reported low legal income, and 81.4% were ever homeless. Homelessness (AOR=0.31), crack, cocaine and heroin ever use (AOR=2.46, 2.11 & 2.35 respectively), recent heroin (AOR=0.42) and injection drug use (AOR=2.03) were significantly associated with being seen on the van. Males (AOR=1.96) and those reporting prior knowledge of HBV vaccine were more likely seen in the storefront (AOR=2.04). There were no differences in vaccine acceptance by site. These preliminary findings suggest that personnel availability did not impede vaccination efforts and thus had no effect on vaccine acceptance by site. Additionally, a research setting, particularly a mobile unit, may provide an ideal environment for identifying and vaccinating those at risk for HBV infection.