What is influenza (also called flu)?
How do flu vaccines work?
Who should get vaccinated this season?
When should I get vaccinated?
Special Consideration Regarding Egg Allergy:
Can the flu vaccine give me the flu?
No, a flu vaccine cannot cause flu illness. Flu vaccines that are administered with a needle are currently made in two ways: the vaccine is made either with a) flu vaccine viruses that have been ‘inactivated’ and are therefore not infectious, or b) with no flu vaccine viruses at all (which is the case for recombinant influenza vaccine). The nasal spray flu vaccine does contain live viruses. However, the viruses are attenuated (weakened), and therefore cannot cause flu illness. The weakened viruses are cold-adapted, which means they are designed to only cause infection at the cooler temperatures found within the nose. The viruses cannot infect the lungs or other areas where warmer temperatures exist.
Different side effects can be associated with the flu shot and nasal spray flu vaccines. These side effects are mild and short-lasting, especially when compared to symptoms of influenza infection.
The flu shot: The viruses in the flu shot are killed (inactivated), so you cannot get the flu from a flu shot. Some minor side effects that could occur are:
- Soreness, redness, or swelling where the shot was given
- Fever (low grade)
The nasal spray: The viruses in the nasal spray vaccine are weakened and do not cause severe symptoms often associated with influenza illness. In children, side effects from the nasal spray can include:
- Runny nose
- Muscle aches
In adults, side effects from the nasal spray vaccine can include
- Runny nose
- Sore throat
If these problems occur, they begin soon after vaccination and are mild and short-lived. Almost all people who receive influenza vaccine have no serious problems from it. However, on rare occasions, flu vaccination can cause serious problems, such as severe allergic reactions. People who think that they have been injured by the flu shot can file a claim for compensation from the National Vaccine Injury Compensation Program (VICP).
More information about the safety of flu vaccines is available at Influenza Vaccine Safety.
• Misconceptions about Seasonal Influenza & Influenza Vaccines
• Vaccine Effectiveness – How Well Does the Flu Vaccine Work?