October 2007, Volume 37 Number 10 , p 47 - 47
What is influenza?
Influenza, or the flu, is caused by a virus. The flu virus, which easily spreads from person to person in coughs and sneezes, affects people of all ages. Most people who get it are sick for only a few days, but others get sick enough to need medical care, and some die. Older adults and people with weak immune systems or chronic illnesses are especially likely to become seriously ill. A fever, headache, tiredness, sore throat, dry cough, chills, and body aches are typical ...