Flu shot: Your best bet for avoiding influenza
Getting a flu shot often protects you from coming down with the flu. And although the flu shot doesn't always provide total protection, it's worth getting.By Mayo Clinic Staff
This year's annual flu shot will offer protection against the H1N1 flu virus, in addition to two other influenza viruses that are expected to be in circulation this flu season. A vaccine that protects against four strains of the virus will also be available, as will a high-dose flu vaccine for adults age 65 and older.
Influenza is a respiratory infection that can cause serious complications, particularly to young children, older adults and people with certain medical conditions. Flu shots are the most effective way to prevent influenza and its complications. The Centers for Disease Control and Prevention (CDC) recommends that everyone 6 months of age or older be vaccinated annually against influenza.
Here are the answers to common questions about flu shots:
When is the flu vaccine available?
Because the flu vaccine is produced by private manufacturers, its availability depends on when production is completed. For the 2017-2018 flu season, manufacturers have indicated shipments began in August and will continue throughout October and November until all vaccine is distributed. Doctors and nurses are encouraged to begin vaccinating people as soon as the flu vaccine is available in their areas.
It takes up to two weeks to build immunity after a flu shot, but you can benefit from the vaccine even if you don't get it until after the flu season starts.
Why do I need to get vaccinated every year?
New flu vaccines are released every year to keep up with rapidly adapting flu viruses. Because flu viruses evolve so quickly, last year's vaccine may not protect you from this year's viruses.
After vaccination, your immune system produces antibodies that will protect you from the vaccine viruses. In general, though, antibody levels start to decline over time — another reason to get a flu shot every year.
Who should get the flu vaccine?
The CDC recommends annual influenza vaccinations for everyone age 6 months or older. Vaccination is especially important for people at high risk of influenza complications, including:
- Pregnant women
- Older adults
- Young children
Children between 6 months and 8 years may need two doses of the flu vaccine, given at least four weeks apart, to be fully protected. Check with your child's health care provider.
Chronic medical conditions also can increase your risk of influenza complications. Examples include:
- Cancer or cancer treatment
- Chronic obstructive pulmonary disease (COPD)
- Cystic fibrosis
- Kidney or liver disease
Who shouldn't get a flu shot?
Check with your doctor before receiving a flu vaccine if:
Sept. 19, 2017
You're allergic to eggs. Most types of flu vaccines contain a small amount of egg protein. If you have an egg allergy, you can receive the flu shot without any additional precautions. If you have a severe egg allergy, you should be vaccinated in a medical setting and be supervised by a doctor who is able to recognize and manage severe allergic conditions.
There are also flu vaccines that don't contain egg proteins, and are Food and Drug Administration (FDA) approved for use in people age 18 and older. Consult your doctor about your options.
- You had a severe reaction to a previous flu vaccine. The flu vaccine isn't recommended for anyone who had a severe reaction to a previous flu vaccine. Check with your doctor first, though. Some reactions might not be related to the vaccine.
See more In-depth
- Frequently asked questions 2017-2018 influenza season. Centers for Disease Control and Prevention. https://www.cdc.gov/flu/about/season/flu-season-2017-2018.htm. Accessed Aug. 29, 2017.
- Hibberd PL. Seasonal influenza vaccination in adults. https://www.uptodate.com/contents/search. Accessed Aug. 25, 2017.
- Key facts about seasonal flu vaccine. Centers for Disease Control and Prevention. https://www.cdc.gov/flu/protect/keyfacts.htm. Accessed Aug. 29, 2017.
- Vaccine effectiveness — How well does the flu vaccine work? Centers for Disease Control and Prevention. https://www.cdc.gov/flu/about/qa/vaccineeffect.htm. Accessed Sept. 14, 2017.
- Centers for Disease Control and Prevention, et al. Prevention and control of influenza with vaccines: Recommendations of the advisory committee on immunization practices, United States, 2017-18 influenza season. MMWR. 2017;66:1. https://www.cdc.gov/mmwr/volumes/66/rr/rr6602a1.htm. Accessed Aug. 24, 2017.