Vaccine facts

Your best defense against the flu is to get vaccinated. Any flu infection can lead to serious complications, hospitalization, or death, even in healthy individuals. Therefore, getting vaccinated is a safer choice than risking illness to get immune protection.

The flu vaccine is available in several forms.

• The flu vaccine is usually given by shot, most often into a muscle in the arm. This form of the vaccine has killed virus. It's approved for most people older than 6 months of age. Children ages 6 months to 8 years who have never been vaccinated need 2 doses given 1 month apart. This is to build up protection. Get the first dose as soon as it's available so that the second dose is given by the end of October. After the first flu season, your child will need only 1 dose for future flu seasons.

• A nasal spray is also a choice for healthy, nonpregnant people 2 to 49 years old. It's made of live but weakened flu virus. It can be taken at the same time as other vaccines (live or non-live). With a live vaccine, it should be spaced at least four weeks apart. However, there is no recommended spacing period between nasal spray flu vaccine and non-live vaccines.

• A needle-free device called a jet injector can give a 2-dose flu vaccine through the skin into the muscle. This may be a choice for people 18 to 64 years old.

A flu vaccine is especially important for people who are more likely to have problems including a hospital stay and death if they get the flu. This includes:

• Children younger than 5 years, and especially younger than 2 years

• People 65 years and older

• Those with long-term (chronic) health conditions or a weak immune system

• Anyone who lives in a nursing home or care facility

• Pregnant people and people who have had a baby in the last 2 weeks

• People from certain ethnic minority groups including non-Hispanic Black people, Hispanic or Latino people, and American Indian and Alaska Native people

• People with blood disorders (such as sickle cell disease)

• People with heart, kidney, liver diseases and endocrine disorders like diabetes

• People with a body mass index of 40 or more

• People younger than 19 years old on long-term aspirin- or salicylate-containing medications.

• People with a weakened immune system due to

  • Diseases such as people with HIV or AIDS,

  • Certain cancers such as leukemia

  • Receiving chemotherapy or radiation treatment for cancer

  • Have chronic conditions that require long-term corticosteroids or other immunosuppressant drugs

Even if you don't fall into any of the above groups, you should still get the vaccine if you want to prevent the flu.

Talk with your healthcare provider first

Some people shouldn't be vaccinated for the flu before talking with their healthcare provider, the CDC says. These are reasons to talk with your healthcare provider:

• You developed Guillain-Barré syndrome in the 6 weeks after getting a flu shot in the past.

• You currently have an illness with a fever. Wait until symptoms get better before getting the vaccine.

• If you had a severe allergic reaction to a previous dose of influenza vaccine.

Children younger than 6 months of age should not be vaccinated against the flu. Flu vaccines haven't been approved for that age group.

People with an allergy to egg-based vaccines may get a flu vaccine as long as it's advised for their age and health status. Severe allergic reactions are unlikely in people with egg allergies. Talk with your healthcare provider about your risk.

Other prevention steps

Flu viruses are spread by contact with droplets sneezed or coughed from an infected person. Breathing in the droplets or aerosols (very small particles in the air) containing flu viruses is the most common way to get the flu. Touching contaminated objects such as doorknobs or handrails on the subway or a bus on which droplets have landed also infects many people. A recent study has found that people didn’t have to cough or sneeze to expel flu viruses into the air. It was detectable in the air after normal breathing and talking. Flu viruses can also spread by direct contact with each other, such as by shaking hands or hugging. You can spread the virus to others before you feel sick yourself. The CDC says you are contagious a day before symptoms start and up to 5 days afterward.

You can protect yourself against the flu by doing simple things like washing your hands before eating, not putting your hands near your face or in your mouth, and wearing a mask over your nose and mouth when around others. Washing hands for at least 20 seconds with soap and clean, running water works fine. If soap and water are not available, rub your hands with an alcohol-based hand cleaner that contains at least 60% alcohol. If someone in your family has the flu, you can help prevent it from spreading by wearing a mask and by cleaning surfaces with a solution of 1 tablespoon of bleach to 1 gallon of water.

Common questions

Can I get the flu from the flu vaccine?

It's impossible to get the flu from the flu vaccine. The vaccine does not contain a form of the flu virus that can give you the flu. The injected form of the vaccine is made from pieces of dead flu virus cells. After getting the vaccine, some people have mild flu-like symptoms as a side effect. This is not the same thing as having the flu.

How does the flu vaccine protect against the flu?

When you get the flu vaccine, your body reacts and makes antibodies that give you immunity against the virus.

Why should I get the flu vaccine every year?

The main reason you should be re-vaccinated each year is that the flu virus is constantly changing into new strains. This is the reason why you won't develop life-long protection after having the flu vaccine. Each year the CDC tries to figure out which flu strains will have the biggest effect. The CDC works with vaccine makers to create the specific vaccine that will fight the predicted strains for that year. Also, a person’s immune protection from vaccination declines over time. Therefore an annual vaccination provides “optimal” or best protection against the flu.

What are my options for covering the cost of the flu vaccine?

If you are concerned about the cost of a flu vaccine, check with your local health department for places near you where free flu shots are given. Many insurers also cover flu vaccines at no cost to their members.

Can antibiotics help treat the flu?

Antibiotics are only effective against bacteria, not against viruses. So, unless you have a bacterial infection of airways along with flu, taking antibiotics won't help.