In February 1985, a fact sheet on HBV and hepatitis D virus (HDV) was distributed to all inmates and staff, and participation in an HBV screening and vaccination program was solicited. Eighty-eight percent of the inmates agreed to participate. Risk factors for HBV among prisoners include age greater than 30 years, prior history of HBV, and intravenous drug use (IVDU). All participants were healthy at the time of screening, thus, the anti-delta positive results presumably represent past infection. Measures to protect against HBV infection, such as use of hepatitis B vaccine, are effective in preventing HDV infection. Implementation of HBV preventive guidelines in correctional facilities should reduce the risk of HDV. 2 tables and 13 references