Evaluation of Vaccines for the Prevention of Pneumonia in Children in Developing Countries

This paper evaluates vaccines designed to prevent pneumonia among children in developing countries. Additionally the article discusses the measurement of vaccine efficacy as well as the potential of vaccine trials to provide information on the etiology of pneumonia and the need for an antibiotic treatment for various categories of acute respiratory infections (ARI). The three approaches to pneumococcal vaccine development include: 1) polysaccharide vaccines; 2) protein-polysaccharide conjugate vaccines; and 3) vaccines based on common protein antigens. The trial design was performed by individual randomization and randomization in clusters. Vaccines were evaluated in terms of the protection they provide against diseases with an unknown pathogen. The clinical and radiologic evaluation of pneumococcal vaccine trials served three related functions: 1) defining the ability of the vaccines to prevent severe pneumonia; 2) measuring the impact of the vaccine on the total burden of pneumonia that is defined by the World Health Organization; and 3) subdividing documented ARI episodes along clinical and radiological lines. Pneumococcal vaccine trials are essential in understanding the nature of pneumococcal disease among children in developing countries as well as the public health utility of vaccines for its prevention.