Flu (Influenza)

The flu is a contagious respiratory sickness caused by a virus. The flu spreads easily when an infected person coughs, sneezes, or talks. Less often, it can spread if someone touches a surface that has influenza virus on it and then touches their mouth, nose, or eyes.source: ¹

Seasonal flu vaccines are the best way to protect yourself and your child from flu and, if you get the flu, from being so sick that you have to see a doctor or go to the hospital.source: ² Children younger than 5 years old—especially those younger than 2—are at higher risk of developing serious flu-related illness. There are many vaccine options available to protect kids against flu.source: ³ (1) Flu shots can be given to kids ages 6 months and older. (2) The nasal spray vaccine can be given to kids 2 years of age and older. The nasal spray vaccine can be given to children who are healthy, without certain underlying medical conditions.source: ⁴ Your child's doctor can tell you which vaccine is right for your child.source: ⁵

Flu is much more serious than the common cold.source: ⁶ For instance, during the 2022–2023 flu season, for every 100,000 children under age 5, 11,443 went to the doctor because of flu, 119 went to the hospital, and one died.source: ⁷ Children are twice as likely as adults 65 years and older to get sick from flu.source: ¹ A seasonal flu vaccine can lower the risk of getting the flu by about 40%–60% when the type of flu virus that is circulating is well-matched to the ones used in that year’s vaccine.source: ⁸ A flu vaccine can also reduce the severity of illness and lower the risk of flu-related hospitalization. Getting a yearly flu vaccine is the best way to protect your child from flu.source: ⁸

Most people who get the flu have a mild illness. But for many, it can be serious—and even deadly. Babies and young kids are especially at risk for serious complications from flu. Between 4,900 and 51,000 people died from flu every year between 2010 and 2023.source: ⁹

It's especially important for people who are at higher risk of developing serious complications from the flu to get a vaccine every year. This includes kids younger than 5 years—and especially kids younger than 2 years.source: ¹⁰

Most people have no side effects from a flu vaccine. If there are side effects, they are usually mild, last 1–3 days, and might include pain, swelling, or redness where the shot was given, headache, muscle aches, fever, or an upset stomach. Side effects from the nasal spray vaccine may include a runny nose, wheezing, headache, vomiting, and muscle aches. Although some side effects from a flu vaccine are similar to those from flu disease, a flu vaccine can't cause the flu. This is because vaccines are either made with a dead or weakened virus or made with proteins from an influenza virus. The nasal spray vaccine also cannot cause the flu because the viruses it contains are weakened and designed to only reproduce in the nose and not warmer parts of your body.source: ¹⁸

Your child needs a flu vaccine every year once they are 6 months old.source: ¹⁹ Getting a flu vaccine every year is important because flu viruses are constantly changing. Every year, updated flu vaccines provide the best protection against the flu viruses that research suggests might be most common in the next flu season.source: ¹⁶

Kids can get a flu vaccine at the same time as other vaccines.source: ²⁰ Pregnant women can help protect their newborn from flu by getting vaccinated while pregnant. Flu vaccination during pregnancy can protect babies for several months after birth against flu and flu-related hospitalizations because the pregnant parent passes antibodies onto the developing baby during pregnancy.source: ²¹

Some kids may need two doses of flu vaccine. This includes kids 6 months through 8 years who are getting a flu vaccine for the first time, and kids who have only ever gotten one dose of flu vaccine. The first dose should be given as soon as the vaccine becomes available, usually in September or October, but can be as early as July or August.source: ^5,source: ^10,source: ²²

Try to get yourself and your child vaccinated against flu by the end of October before flu season begins.source: ⁵ It takes 2 weeks for your body to develop immunity after receiving a flu vaccine. So, it's best to get a flu vaccine before flu starts to spread in your community. Although it is best to get a flu vaccine by the end of October, the vaccine can still provide protection throughout the flu season (fall and winter).source: ²³