Pneumococcal otitis media and pneumococcal vaccines, a historical perspective

Although pneumococcal otitis media was recognized in the 19th century, the illness stimulated little interest in prophylaxis until recently. Whole cel l vaccines of killed pneumococci, developed to prevent pneumonia, were repl aced by vaccines of capsular polysaccharides following demonstration of the ir antigenicity in adults. Failure of the latter to stimulate antibodies in infants and young children and demonstration of the efficacy of capsular p olysaccharide-protein conjugate vaccines in preventing infection with Hemop hilus influenzae type b has led to the development of polyvalent pneumococc al polysaccharide-protein conjugate vaccines. Preliminary studies have show n them to be highly effective in preventing invasive pneumococcal disease i n the first 2 years of life, and studies of their impact on otitis media ar e currently in progress. (C) 2000 Elsevier Science Ltd. All rights reserved .