Flu Shot

Source: MedlinePlus Health Topics, U.S. National Library of Medicine

Last synced 8/14/2026Status: primary verified

What is the flu? The flu (influenza) is a respiratory infection. It is caused by influenza viruses that infect your nose, throat, and lungs. These viruses can spread from person to person. Most people with the flu get better on their own, without medical care. But for some people, the flu is serious. It can cause complications and sometimes even death. People who are 65 and older, under age 5, pregnant, or have certain health conditions are at higher risk of flu complications. Getting vaccinated against the flu each year is best way to lower your risk of the flu and its complications. What are the benefits of getting a flu shot? There are many reasons to get a flu shot each year: It may keep you from getting sick with the flu. If you do get the flu, it may be less severe. You may also be less likely to have complications or need to be hospitalized with the flu. If you have certain chronic health conditions, getting a flu shot may help prevent the flu from making your condition worse. For example, if you have COPD or diabetes , the flu can worsen your condition so much that you might need to be hospitalized. Getting a flu shot can lower this risk. Getting the vaccine during pregnancy not only helps protect you from the flu during and after pregnancy. It also helps protect your baby from flu during their first few months of life. It has been shown to lower the risk of severe life-threatening flu in children. It may also protect the people around you, including those who are at higher risk of complications. How do flu shots work? The flu vaccine causes your immune system to make antibodies about two weeks after you get the shot. These antibodies provide protection against infection with the flu viruses that are in the vaccine. Who needs a flu shot? The U.S Centers for Disease Control and Prevention (CDC) recommends annual flu shots for everyone 6 months and older, with a few rare exceptions. Flu shots are especially important for people who are at high risk of developi

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This information is for general education and is not medical advice. Always talk to a licensed U.S. clinician about your situation, medications, or treatment decisions.