The incidence and type of reactions to plain and adsorbed DTP vaccines.

The incidence and type of reactions after administration of plain and adsorbed diphtheria-tetanus-pertussis vaccine were recorded in a blind controlled prospective study of 2041 vaccinations in 1075 infants receiving routine childhood immunization. There was no significant difference in the total incidence or type of general reactions after plain and adsorbed vaccine, but local reactions were significantly less frequent after plain vaccine. General reactions were recorded after 41.5% of vaccinations with plain vaccine and after 40.8% of vaccinations with adsorbed vaccine. Local reactions were reported in 66.7% and 76.5% of recipients respectively. The most commonly reported systemic reactions were irritability and fever. Three recipients of plain vaccine and one of adsorbed vaccine suffered hyporesponsiveness or collapse. One recipient of each vaccine suffered a convulsion. No persisting sequelae were recorded.