Associations of prevaccination antibody levels with adverse reactions to pneumococcal and influenza vaccines administered simultaneously in the elderly.

The association of prevaccination antibodies with the adverse reactions seen after vaccination was studied in 85 elderly subjects (65-90 years) vaccinated simultaneously with pneumococcal and influenza vaccines. The subjects with a temperature rise (9% of vaccinees) had significantly higher prevaccination antibody levels to pneumococcal capsular polysaccharides (PPSs) than those without a temperature rise; no difference was seen in their haemagglutination inhibiting (HI) influenza virus antibody levels. Pain in the left arm (the pneumococcal vaccine injection site) occurred in 45% of the subjects and was likewise associated with elevated PPS antibody levels. Pain at the site of influenza vaccine injection (the right arm) seen in 33% of the vaccinees was significantly more common among those who had previously received influenza vaccine, but was not associated with elevated HI antibody levels. In conclusion, prevaccination pneumococcal but not influenza antibodies were associated with both systemic and local reactions following vaccination.