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Division of Disease Control

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The Flu Vaccine

Getting a flu shot is the single best way to protect against the flu.

The flu vaccine protects you from getting sick
The flu vaccine can protect you from getting sick from influenza viruses, and also helps prevent you from unknowingly spreading it around. The flu vaccine contains killed flu viruses. It cannot cause the flu, and it will help prepare the body to fight off infection from the flu virus.

The flu vaccine is usually given with a needle in the arm (injectable vaccine). For the 2017-2018 flu season, the Centers for Disease Control and Prevention (CDC) no longer recommends the live attenuated vaccine (LAIV), also known as the nasal spray vaccine, because it was not as effective.

The most effective way to prevent the flu is to receive the injectable vaccine (inactivated influenza vaccine or IIV) or the recombinant influenza vaccine (RIV). 

Everyone should get a flu vaccine
The CDC recommends that everyone 6 months and older get a flu vaccine.

Some people have a high risk for serious flu-related complications, or live with or care for people at high risk for having flu-related complications. These people should make sure to get a flu shot:

  • Pregnant women
  • Children younger than 5, but especially children younger than 2 years old
  • People age 50 and older
  • People with certain chronic medical conditions
  • People who live in nursing homes and other long-term care facilities
  • People who live with or care for those at high risk for complications from flu, including:
  • Health care workers
  • 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)

When should I get a flu vaccine?
The best time to get a flu vaccine is as soon as it becomes available in your community – usually in August, September or October. However, getting a flu vaccine in the winter months will still provide some protection for the flu season, which can sometimes last into the spring.

Should pregnant women get the flu vaccine?
Yes. It is safe and recommended for women to get a flu vaccine during pregnancy. Pregnant women are more likely to have serious complications from the flu, such as pneumonia and preterm labor, which can put the baby at risk. The vaccine will help protect both mother and baby.

Why get a flu vaccine?
Why get a flu shotGetting a flu vaccine is not only the best way to protect YOU, it is also the best way to protect others.  If you don’t catch the flu, then you won’t spread it to your friends or your family. 

Babies younger than 6-months old cannot get the flu vaccine, but they are at high risk for serious illness and flu complications. The best way to protect them is to make sure their caregivers and all members of their household are vaccinated.

Where can I get a flu vaccine?

For Adults
The best place to get a flu vaccine is at your doctor’s office.  You can also get a flu shot at many local pharmacies. If you are an uninsured adult, you can get free flu vaccine at a community flu clinic.

For Children
The best place for children to get a flu shot at their doctor’s office.  Children who are eligible for the Vaccine For Children (VFC) program can receive flu shots for free from doctors who participate in the VFC program.

How does the flu vaccine work?
Flu vaccines cause the body to develop antibodies. These antibodies protect against infection from the viruses that cause the flu.  It takes about two weeks after vaccination for antibodies to develop in the body and provide protection against infection.  In the meantime, you are still at risk for getting the flu.  As a result, it is useful to get vaccinated in the fall, before the flu season beings.

The flu vaccine is updated each year because viruses change from year to year.

What are the risks from getting a flu vaccine?
You cannot get the flu from a flu vaccine. The risk of a flu vaccine causing harm is extremely small. Similar to different medications, the flu vaccine has the potential to cause problems like allergic reactions. However, this is rare and the majority of people who get the flu vaccine have no problems from it.

The most common side effect of the flu vaccine in adults is soreness at the spot where the shot was given, which usually lasts less than two days.  The soreness is often caused by a person’s immune system making protective antibodies to the dead viruses in the vaccine.  These antibodies cause the body to fight against flu. The needle stick may also cause some soreness at the injection site.

Some people, including children, also have symptoms such as a low-grade fever, muscle pain, and feelings of discomfort or weakness. If these problems occur, they are very uncommon and usually begin soon after the shot and last one or two days.

Can people with egg allergies receive a flu shot?
People with egg allergies who have experienced hives after egg exposure can receive the flu vaccine and do not have to be watched for 30 minutes after getting the vaccine. Those with a severe egg allergy who have experienced symptoms other than hives after being exposed to eggs, such as respiratory distress, lightheadedness, or have used epinephrine, can also get the flu vaccine but should be watched by a health care provider after getting the vaccine in the event that they experience an allergic reaction.


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