Pathogenesis and sequelae of respiratory infections.

Bacterial pneumonia remains a major health threat, with particular risk for infants in developing countries. The effective design of strategies that minimize the morbidity and mortality from pneumonia requires an awareness of the host defense mechanisms that function to prevent respiratory infections. In this review the normal immune host defenses and the abnormalities in this process that promote the development of lower respiratory bacterial infections will be briefly reviewed. A brief discussion will focus on a complication of respiratory infections, asthma, which can follow viral illness and also be a significant problem for children.