Polyvalent Pneumococcal Vaccine Given Alone and in Combination with Bivalent Influenza Virus Vaccine

Sixty-eight normal subjects were immunized by the intramuscular route with either hexavalent pneumococcal polysaccharide vaccine, bivalent influenza virus vaccine, or a combined pneumococcal polysaccharide and influenza virus vaccine. Serum specimens collected before and 3 weeks after inoculation were analyzed by radioimmunoassay and hemagglutination-inhibition assay to determine antibody response. Although both the pneumococcal vaccine and the combined vaccine induced greater mean pneumococcal antibody titers following immunization, the titers of five of the six pneumococcal types were lower in the combined vaccine group. Postimmuni-zation influenza virus antibody titers were similar in subjects who received the influenza virus-alone vaccine or the combination vaccine. Local and systemic side effects occurred in more subjects of the combined vaccine group than in those of the single vaccine groups; however, fewer effects appeared in the individual pneumococcal vaccine group than in the influenza virus vaccine group.