Influenza Vaccination Trends Among Adults 65 Years or Older in the United States, 1989-2002

Abstract

Influenza causes significant morbidity and mortality in adults. Illnesses caused by influenza occur in an average of 5% to 20% of the US population annually.¹ About 50% of those who become ill seek medical care, 1% of those who seek medical care are hospitalized, and 8% of those who are hospitalized die as a consequence of influenza.² Overall, on average, each year approximately 226 000 patients are hospitalized for influenza-related respiratory or circulatory illnesses,³ and approximately 36 000 individuals die of influenza-associated causes, more than 90% of whom are elderly (65 years or older).^4,5