Even healthy people need a flu vaccine.

Influenza (flu) is a contagious disease which can lead to serious illness, including pneumonia. Even healthy people can get sick enough to miss work or school for a significant amount of time or even be hospitalized. An annual flu vaccine is recommended for everyone 6 months of age and older. Pregnant women, young children, older people, and people with certain chronic medical conditions like asthma, diabetes and heart disease are at increased risk of serious flu-related complications, so getting a yearly flu vaccine is especially important for them.


The flu vaccine is safe. Hundreds of millions of Americans have safely received flu vaccines over the past 50 years, and there has been extensive research supporting the safety of seasonal flu vaccines. Each year, CDC works closely with the U.S. Food and Drug Administration (FDA) and other partners to ensure the highest safety standards for flu vaccines.

The most common side effects of flu vaccines are mild.

The flu vaccine cannot cause flu illness; however, it can cause mild side effects that may be mistaken for flu. Common side effects from the flu shot include soreness, redness, and/or swelling from the shot, headache, fever, muscle aches, and nausea. These side effects are NOT the flu. If experienced at all, these effects are usually mild and last only 1-2 days.

Even if I get sick, won’t I recover quickly?

Not necessarily. Influenza can be serious and anyone can become sick with flu and experience serious complications, including active and healthy kids, teens and adults. Even if you bounce back quickly, however, others around you might not be so lucky. You could spread your illness to someone who is more vulnerable to flu. Some people can be infected with the flu virus, but have no symptoms. During this time, you can still spread the virus to others. Don’t be the one spreading flu to those you care about.

Can’t I wait and get vaccinated when/if flu hits my community?

It is best to get vaccinated before flu begins to spread. It takes about two weeks after vaccination for antibodies to develop in the body and provide protection against the flu, so the sooner you get vaccinated, the more likely it is that you will be protected once flu begins to circulate in your community.


Even if you got a flu vaccine, there are reasons why you might still get flu or a flu-like illness.

  • You may have been exposed to a non-flu virus. The flu vaccine can only prevent illnesses caused by flu viruses. It cannot protect against other viruses that may cause symptoms similar to flu, like the common cold.
  • You might have been exposed to flu after you got vaccinated, but before the vaccine took effect. It takes about two weeks after you receive the vaccine for your body to build protection against the flu.
  • You may have been exposed to an influenza virus that was very different from the viruses included in that year’s vaccine. The flu vaccine protects against the influenza viruses that research indicates will cause the most disease during the upcoming season, but there can be other flu viruses circulating.
  • Unfortunately, however, some people who get a flu vaccine may still get sick. How well the flu vaccine works (or its ability to prevent flu) can range from season to season and also can vary depending on who is being vaccinated. However, if you do get sick, flu vaccination might make your illness milder than it would have been otherwise


The minor pain of a flu shot is nothing compared to the suffering that can be caused by the flu. A flu vaccine reduces your risk of illness, hospitalization, and can prevent you from spreading the virus to your loved ones. So, whatever little discomfort you feel from the minor side effects of the flu shot is worthwhile to avoid the flu. You need to get a flu vaccine every year.

There are two reasons for getting a flu vaccine every year:

  1. Flu viruses are constantly changing and so flu vaccines may be updated from one season to the next. You need the current season’s vaccine for the best protection.
  2. A person’s immune protection from the vaccine declines over time. Annual vaccination is needed for the best protection.