Content

Flu, also called influenza, is an infection of the nose, throat and lungs, which are part of the respiratory system. The flu is caused by a virus. Most people with the flu get better on their own. But influenza can cause serious complications for some groups of people.

Getting a flu vaccine is the best way to prevent the flu and its complications for almost everyone. The flu vaccine can lower the risk of getting the flu. It also can lower the risk of having serious illness from the flu and needing to stay in the hospital or dying of the flu.

This year's seasonal flu vaccines each provide protection against three influenza viruses that researchers expect to be most common this flu season.