National Institutes of Health

The primary NIH organization for research on Flu Shot is the National Institute of Allergy and Infectious Diseases

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Flu Shot

Also called: Flu vaccine

Summary

Flu is a respiratory infection caused by a number of viruses. Most people with the flu get better on their own. But it can be serious. It can cause complications and sometimes even death. Getting the flu vaccine every year is the best way to lower your chance of getting the flu and spreading it to others.

The flu vaccine causes antibodies to develop in your body about two weeks after you get it. These antibodies provide protection against infection with the viruses that are in the vaccine.

Flu vaccines can either be shots or nasal sprays. There is also a high-dose version for people 65 and older. Ask your health care provider which one is right for you.

Everyone 6 months of age and older should get a flu vaccine every season. People with egg allergies should check with their doctors before getting a vaccine. Other exceptions are people who have