Planning for a second (23 valent) generation pneumococcal vaccine. With special reference to new developments in our understanding of the structure and biology of polysaccharides.

The epidemiologic and experimental data upon which the proposed second and more expanded formulation for the pneumococcal capsular polysaccharide was based has been reviewed. The use of a functional (opsonization) and quantitative (radioimmunoassay) for assaying the human serum antibody response in order to predict the efficacy of pneumococcal vaccine should permit further examination of its usefulness in various clinical settings. New developments in the area of improved pneumococcal and other polysaccharide vaccines were examined.