"Influenza, also known as flu, is a viral infection in the nose, throat, and lungs caused by a number of different strains of the influenza virus. For the very young, those with chronic conditions, those with compromised immune systems, and the elderly, influenza often requires treatment by a health care professional. This Statistical Brief presents estimates based on the Household Component of the Medical Expenditure Panel Survey (MEPS-HC) on health care use and expenditures for influenza treatment among the U.S. civilian noninstitutionalized population. Average annual estimates (in 2003 dollars) for the period 2001--2003 are shown by age, chronic condition status for adults, and type of service. The brief highlights chronic condition status for adults because people with chronic conditions (such as heart disease, asthma, and diabetes) are at greater risk for influenza complications. Data for three years were combined to improve the precision of the estimates, and expenditure data for 2001 and 2002 were adjusted to 2003 dollars using the Gross Domestic Product medical care price deflator. All differences between estimates noted in the text are statistically significant at the 0.05 level or better."
Medical Expenditure Panel Survey (U.S.) Statistical Brief No. 116
Agency for Healthcare Research and Quality, Medical Expenditure Panel Survey: http://www.meps.ahrq.gov/