Influenza: The Disease

Influenza (the flu) is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness, and at times can lead to death. The best way to prevent the flu is by getting a flu vaccination each year. Every year in the United States, on average 5% to 20% of the population gets the flu; more than 200,000 people are hospitalized from flu complications, and; about 36,000 people die from flu. Some people, such as older people, young children, and people with certain health conditions, are at high risk for serious flu complications. ---The Centers for Disease Control and Prevention (CDC)

Seasonal Influenza Information for Health Professionals

Recommendations of the Advisory Committee on Immunization Practices (ACIP)

Information for Specific Groups