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Every year, millions of people get the flu. The good news is that the seasonal flu vaccine can lower the risk of getting the flu by about half. Getting the yearly flu vaccine is the best way to protect yourself from the flu.
Most people who get the flu have a mild illness. But for some, it can be serious — and even deadly. Serious complications from the flu are more likely in babies and young children, pregnant women, older adults, and people with certain long-term health conditions — like diabetes or asthma.
Getting vaccinated every year is the best way to lower your chances of getting the flu. Flu vaccines can’t cause the flu. Keep in mind that getting the flu vaccine also protects the people around you. So when you and your family get vaccinated, you help keep yourselves and your community healthy.
This is especially important if you spend time with people who are at risk for serious illness from the flu — like young children or older adults. Learn more about how vaccines help protect your whole community.
The flu is caused by a virus. Common symptoms of the flu include:
Some people with the flu may throw up or have diarrhea (watery poop) — this is more common in children than adults. It’s also important to know that not everyone with the flu will have a fever.
The flu is worse than the common cold. It’s a common cause of problems like sinus or ear infections. It can also cause serious complications like:
The flu is contagious, meaning it can spread from person to person. The flu can spread when:
People can spread the flu before they know they’re sick — and while they have the flu. Learn more about the flu.
Everyone needs to get the flu vaccine every year. It’s part of the routine vaccine schedules for children, teens, and adults.
It’s important to get the flu vaccine every year. That’s important for 2 reasons: first, immunity (protection) decreases with time. Additionally, the flu viruses are constantly changing — so the vaccine is often updated to give the best protection.
It’s especially important for people who are at high risk of developing complications from the flu to get the vaccine every year. People at high risk for complications from the flu include:
Aim to get your flu vaccine by the end of October
Try to get the flu vaccine by the end of October. It takes 2 weeks for your body to develop immunity. So it’s best to get the flu vaccine before the flu starts to spread in your community.
If you don’t get the vaccine by the end of October, that doesn’t mean you shouldn’t get it — getting vaccinated later can still help protect you from the flu. You can get vaccinated at any time throughout the flu season.
It’s also very important for people who spend a lot of time with people at high risk for complications from the flu to get the vaccine — for example, health care professionals and caregivers.
Talk with your doctor about how to protect your family from the flu.
Children younger than 6 months should not get the flu vaccine.
Be sure to tell your doctor before getting vaccinated if you:
If you’re sick, you may need to wait until you’re feeling better to get the flu vaccine.
Side effects are usually mild and go away in a few days. These side effects aren’t the flu — the flu vaccine can’t cause the flu.
Side effects from the flu vaccine may include:
Serious side effects from the flu vaccine are very rare.
Like any medicine, there's a very small chance that the flu vaccine could cause a serious reaction. Keep in mind that getting the flu vaccine is much safer than getting the flu. Learn more about vaccine side effects.
Vaccine Information Statements (VISs) have detailed information about recommended vaccines.
Last reviewed: January 2018