Response to pneumococcal vaccination in normal and post-infected Nigerians

Twelve patients who had recovered from pneumococcal infections and 12 household controls were given a polyvalent pneumococcal vaccine. Adequate amounts of antibody were detected by radioimmunoassay before immunisation in controls and patients. More controls responded to nine pneumococcal polysaccharides than did patients. A transient state of unresponsiveness to vaccine may exist in some patients for a period of 4-6 weeks after infection. The high concentrations of antibody before immunisation in adult controls suggest adequate herd immunity to the endemic serotypes in the adult population.