ABSTRACT
A campaign against hepatitis B was launched in 1985 in Latium Region, Italy, aimed at hospital workers, newborns of HBsAg positive mothers, hemodialysis patients, thalassemics and hemophiliacs. Subsequently, since the beginning of 1987 other at risk categories were included, namely households of HBsAg positive carriers, subjects with accidental exposure to Hepatitis B virus (HBV) (i.e exposure to street syringes), health care personnel working outside the hospital setting such as dentists, private clinics and laboratory workers, etc. A protocol was defined by the Regional Epidemiologic Unit (Osservatorio Epidemiologico Regionale) in order to evaluate the immunogenicity and safety af the two plasma-derived (pd) vaccines registered in Italy, MSD and Pasteur, in field conditions. Subjects belonging to these at risk categories were distributed among 21 hospital based vaccination units, to which the two vaccines were randomly allocated. Subjects were considered eligible for vaccination if they were HBsAg negative and Anti-HBs negative or Anti-HBs positive at low titer i.e. less than 20 milli-International units per milliliter. Subjects with insulin dependent diabetes, chronic liver disease or known hypersensitivity to vaccine components were also excluded. Antibody response was checked at six months since the beginning of the vaccination, i.e. after two doses of the MSD and three doses of Pasteur vaccine and expressed in miU/ml by use of Hollinger formula. Pre-vaccination screening, vaccination and post-vaccination anti-HBs testing were offered free of charge.(ABSTRACT TRUNCATED AT 250 WORDS)
