Preventing the Flu: Get Vaccinated
The single best way to prevent the flu is to get a flu vaccination each fall. There are two types of vaccines:
- The "flu shot" – an inactivated vaccine (containing killed virus) that is given with a needle. The flu shot is approved for use in people 6 months of age and older, including healthy people and people with chronic medical conditions.
- The nasal-spray flu vaccine – a vaccine made with live, weakened flu viruses that do not cause the flu (sometimes called LAIV for “Live Attenuated Influenza Vaccine”). LAIV is approved for use in healthy people 5 years to 49 years of age who are not pregnant.
About two weeks after vaccination, antibodies develop that protect against influenza virus infection. Flu vaccines will not protect against flu-like illnesses caused by non-influenza viruses.
When to Get Vaccinated
October or November is the best time to get vaccinated, but getting vaccinated in December or even later can still be beneficial since most influenza activity occurs in January or later in most years. Though it varies, flu season can last as late as May.
Who Should Get Vaccinated?
In general, anyone who wants to reduce their chances of getting the flu can get vaccinated.
People who should get vaccinated each year are:
1. People at high risk for complications from the flu, including:
- Children aged 6 months until their 5th birthday,
- Pregnant women,
- People 50 years of age and older,
- People of any age with certain chronic medical conditions, and
- People who live in nursing homes and other long term care facilities.
2. People who live with or care for those at high risk for complications from flu, including:
- Household contacts of persons at high risk for complications from the flu
- Household contacts and out of home caregivers of children less than 6 months of age (these children are too young to be vaccinated)
- Health care workers.
3. Anyone who wants to decrease their risk of influenza.
Use of the Nasal Spray Flu Vaccine
Vaccination with the nasal-spray flu vaccine is an option for healthy persons aged 5-49 years who are not pregnant, even healthy persons who live with or care for those in a high risk group. The one exception is healthy persons who care for persons with severely weakened immune systems who require a protected environment; these healthy persons should get the inactivated vaccine.
Who Should Not Be Vaccinated
Some people should not be vaccinated without first consulting a physician. They include:
- People who have a severe allergy to chicken eggs.
- People who have had a severe reaction to an influenza vaccination in the past.
- People who developed Guillain-Barré syndrome (GBS) within 6 weeks of getting an influenza vaccine previously.
- Children less than 6 months of age (influenza vaccine is not approved for use in this age group).
- People who have a moderate or severe illness with a fever should wait to get vaccinated until their symptoms lessen.
If you have questions about whether you should get a flu vaccine, consult your health-care provider.
Centers for Disease Control and Prevention, 1600 Clifton Rd, Atlanta, GA 30333, USA