SAFETY AND IMMUNOGENICITY OF AN INACTIVATED HEPATITIS-A VACCINE IN PRESCHOOL-CHILDREN

Young children in day care centers are an important source of hepatiti s A virus (HAV) infection. The safety and immunogenicity of an inactiv ated HAV vaccine was evaluated in 57 children in day care centers. Non immune healthy children were given 0.5 mt of vaccine with subsequent d oses: group A (28 children), second and third doses 1 and 2 months aft er the first; group B (29 children), second and third doses at 1 and 6 months. Antibody to HAV was measured before each dose and 8 months af ter the initial dose. All children developed antibody to HAV. Groups A and B had similar levels of antibody at 2 months; levels were lower i n group B before the third dose and higher 8 months after the first do se. Local reactions after vaccination were reported in 17 children (29 .8%). Minor systemic side effects that cleared spontaneously were obse rved in 27 children (47%).