Background
Each year, on average, some 5% to 20% of United States residents become ill from seasonal flu, and more than 200,000 people are hospitalized for flu-related complications. Most people will have mild illness; however, some individuals are at an elevated risk for developing flu-related complications, including adults 65 years of age and older and people who have certain medical conditions (eg, weakened immune system, heart disease, chronic lung disease). A challenge providing vaccine to many vulnerable people is being able to reach them.



