Clinical and serological reactions after immunization of children in Ghana, West Africa, with the Japanese acellular pertussis vaccine.

A sero-epidemiological survey of pertussis and a field trial with acellular pertussis vaccine was carried out in children in a rural village in Ghana, West Africa. ELISA antibody assays in 109 children aged three months to three years disclosed the rapid disappearance of transplacental maternal antibody in early infancy and the accumulation of seronegative children under three years of age. One hundred and ten children aged three months to three years were immunized with the newly developed acellular pertussis vaccine; 32 were immunized twice and 77 were immunized three times. Serological responses after immunization were measured in both groups. There were no severe adverse reactions attributable to vaccine injections among the children studied.