. "Appendix B: The Burden of Disease Resulting from Acute Respiratory Illness." New Vaccine Development: Establishing Priorities: Volume II, Diseases of Importance in Developing Countries. Washington, DC: The National Academies Press, 1986.
aModified from Bulla and Hitze (1978). Rates in some categories are based on a small number of reporting countries.
Pio et al. (1985) reviewed the results of bacteriological studies on lung aspirates from children (birth to 8 years of age) in developing countries who had pneumonia and no previous antimicrobial treatment. About 55 percent of these aspirates were culture positive for bacteria. Of these, 22.5 percent contained S. pneumoniae, and 11.5 percent contained H. influenzae. Staphylococcus aureus (4.4 percent), mixed infections, or other bacteria accounted for the balance of positive cultures. These proportions may be underestimates because the appropriate lung lesion may not have been reached with the aspiration needle or because laboratory methods may have been inadequate. Lung aspirate sampling may overestimate the significance of bacterial pathogens because of the kinds of patients selected for testing (see above). However, it is not possible to estimate how much these considerations affect the accuracy of available data.