The flu (influenza) is a disease caused by viruses. Each winter many people get the flu. Influenza causes a fever, muscle aches, sore throat, cough, and tiredness that may last for several days. Most children are sick for only a few days, but some children get much sicker and may need to be hospitalized. The disease can usually be prevented by getting a vaccine, commonly called a flu shot. The influenza virus changes from year to year. Because of these changes, protection from the influenza virus usually lasts only for 1 year.
All adults and children over 6 months old should get the flu vaccine.
The flu vaccine can be given as an injection the arm.
A nasal spray called FluMist is another way to get the flu vaccine. The nasal spray contains a weakened, live virus and can be given only to healthy children over 2 and healthy adults who are not pregnant and who are younger than age 50. As with flu shots, your child will need a new dose of FluMist every year. Pregnant women, children under 2 years, people 50 or older, or people who have weakened immune systems, asthma, or some other medical conditions cannot take the nasal spray.
If your child gets the nasal spray vaccine, your child should avoid contact with anyone at risk for at least 1 week to make sure that the live virus isn’t spread to them. If you are thinking about getting the nasal spray for your child, ask your healthcare provider if it is recommended for your child.
Your child should get a new flu shot every year because the vaccine wears off over time, and it may change each year. It’s best to get the new vaccine as soon as it’s available each year, before the start of flu season. However, if the vaccine is still available, it can be helpful to get it anytime during the flu season. Flu season usually starts in October and may last through May.
Mild symptoms after a flu shot include soreness at the site of the shot, fever, and body aches. If your child has the nasal spray flu vaccine, symptoms may include runny nose, nasal congestion or cough, fever, headache, and muscle aches. These problems usually last for 1 or 2 days. Serious complications are very rare.
Thimerosal is a preservative used in some flu shots. Thimerosal contains mercury and can cause reactions in some people. Thimerosal-free vaccine is available if your child is allergic to thimerosal or you are concerned about its safety. The nasal flu vaccine does not contain thimerosal.
Talk with your child’s healthcare provider before your child gets a shot if your child:
Children with long-term health problems such as heart or lung disease should have the shot but not the nasal spray form of the vaccine.
For more information about the vaccine, ask your healthcare provider for an Influenza Vaccine Information Statement.