PNEUMONIA AND INFLUENZA DEATHS DURING EPIDEMICS - IMPLICATIONS FOR PREVENTION

Pneumonia and influenza (P and I) deaths among adults during epidemics of influenza A (H3N2) virus are reviewed and risks of such deaths according to age and presence of chronic disease are estimated from medical records of a large group practice. Thirty-eight deaths occurred among 310 persons hospitalized with P and I. Flu-like symptoms occurred in 30 patients (79%), 26 patients (68%) were > 65 yr, 36 patients (95%) had chronic disease and .apprx. 1/2 were medically stable before the terminal episode. These values were similar to those of P and I deaths during nonepidemic periods. Pneumonia and influenza death rates ranged from < 10 to > 600/100,000 among healthy vs. chronically ill adults. Highest rates (870/100,000) occurred in persons with both cardiovascular and pulmonary disease. Application of these findings to influenza vaccination strategies in clinical practice is discussed.