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Vaccination & Vaccine Safety
Everyone 6 months of age and older should get the flu vaccine. Seasonal flu vaccines have a very good safety track record.
- The flu vaccine is available by shot or nasal spray.
- Get your flu shot or spray as soon as the vaccine is available in your area.
- It is especially important to get the vaccine if you, someone you live with, or someone you care for is at high risk of complications from the flu.
- Mild reactions such as soreness, headaches, and fever are common side effects of the flu vaccine.
- If you experience a severe reaction such as difficulty breathing, hives, or facial swelling, seek medical attention immediately.
Where can I get the vaccine?
Use the Flu Vaccine Finder to find a flu vaccine location near you this flu season. The 2013-2014 vaccine is now available.
How effective is the flu vaccine?
The flu vaccine is the best protection against the flu this season. If you get the flu vaccine, you are 60% less likely to need treatment for the flu by a healthcare provider. Getting the vaccine has been shown to offer substantial other benefits including reducing illness, antibiotic use, time lost from work, hospitalizations, and deaths.
When should I get the vaccine?
Get the vaccine as soon as it is available in your area. Flu season usually peaks in January or February, but it can occur as late as May. Early immunization is the most effective, but it is not too late to get the vaccine in December, January, or beyond.
How should I get the vaccine?
There are two different types of flu vaccines, trivalent and quadrivalent.
Trivalent vaccines protect against 3 strains of the flu, A/H3N2, A/H1N1, and influenza B. Trivalent vaccines are available in:
- Traditional flu shots, approved for anyone 6 months and older
- Intradermal shots, which use a shorter needle, approved for anyone 18-64
- High dose shots approved for people over 65
- Cell based shots created using viruses grown in animal cells and approved for anyone over 18
- Recombinant shots created using DNA technology, approved for people 18-49 with severe egg allergies
Quadivalent vaccines protect against 4 strains of the flu, A/H3N2, A/H1N1, and 2 strains of influenza B. Quadrivalent vaccines are available in:
- Traditional flu shots, approved for anyone 6 months and older
- Nasal spray, approved for healthy people from 2-49, except pregnant women
How long is my flu vaccination good for?
The flu vaccine will protect you for one flu season.
Does the flu vaccine work right away?
It takes about two weeks after vaccination for antibodies to develop in the body and provide protection against influenza virus infection. In the meantime, you are still at risk for getting the flu. That's why it's better to get vaccinated early in the fall, before the flu season really gets under way.
Is the vaccine safe?
Seasonal flu vaccines have a very good safety track record. Although there are possible side-effects to vaccination, the Centers for Disease Control and Prevention and the Food and Drug Administration closely monitor the safety of seasonal flu vaccines.
Should I get the flu vaccine if I’m not feeling well?
If you are sick with a fever, you should wait until your fever is gone before getting a flu shot. However, you can get a flu shot if you have a respiratory illness without a fever, or if you have another mild illness.
The nasal-spray flu vaccine can be given to people with minor illnesses, such as:
- a mild upper respiratory tract infection, with or without a fever.
If you have nasal congestion, you should consider waiting to get the nasal-spray flu vaccine. Nasal congestion may limit the vaccine's ability to reach the nasal lining.
Are there side effects?
Mild side effects usually begin soon after you get the vaccine and last one to two days. Possible mild side effects of the flu shot include:
- Soreness, redness, and swelling at the injection site
- Fainting, mainly in adolescents
Possible mild side effects of the nasal spray include:
- Runny nose
- Muscle aches
Serious side effects usually begin within a few minutes to a few hours after receiving the shot. Possible serious side effects of vaccination include:
- Difficulty breathing
- Swelling around the eyes or lips
- Racing heart
- Behavior changes
- High fever
If you experience any of these reactions, seek medical attention immediately.
How can I report a serious reaction to the vaccine?
Contact your health care provider immediately if you have a serious reaction to the flu vaccine. Your health care provider should report your reaction to the Vaccine Adverse Event Reporting System (VAERS). You can also file a report yourself. All serious reactions should be reported, even if you aren’t sure it was caused by the flu vaccine. VAERS uses this data to help identify serious reactions that may need further investigation.
If your reaction results in a serious injury, you may qualify for compensation from the Vaccine Injury Compensation Program (VICP). VICP provides compensation for vaccine-related injury or death claims for covered vaccines given on or after October 1, 1988.
Can I get the flu from the vaccine?
No, you cannot get the flu from the flu shot or the nasal spray. The flu shot contains inactivated (killed) flu viruses that cannot cause illness. The nasal spray contains weakened live viruses. The weakened viruses only cause infection in the cooler temperatures found in the nose. The viruses cannot infect the lungs or other areas in the body where warmer temperatures exist.
Will I need to pay for the vaccine?
Most health insurance plans cover the cost of vaccines, but you should check with your insurance company before visiting your health care provider. Under the Affordable Care Act, many insurers are required to cover certain preventive services, like the flu vaccine, at no cost to you.
If you do not have insurance or if it does not cover vaccines, help is available.
Is there anyone who should not get the vaccine?
Talk to your health care provider about vaccination if you have:
- A severe allergy to chicken eggs
- A history of severe reaction to a flu vaccination
- A moderate-to-severe illness with a fever (you should wait until you are better to get the vaccine)
- A history of Guillain–Barré Syndrome (a severe paralytic illness, also called GBS)
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- FDA Approves First Quadrivalent Vaccine to Prevent Seasonal Influenza
- Community Immunity (“Herd Immunity”)
- Misconceptions about Seasonal Influenza and Influenza Vaccines
- Vaccine Effectiveness – How Well Does the Flu Vaccine Work?