Your Child's Immunizations: Influenza Vaccine

Why the Vaccine Is Recommended

While the flu vaccine isn't 100% effective, it still greatly reduces a person's chances of catching the flu, which can be very serious, and can make symptoms less severe if someone does still get the flu after immunization.

Even if you or your kids got the seasonal flu vaccine last year, that won't protect you from getting the flu this year, because flu viruses constantly change. That's why the vaccine is updated each year to include the most current strains of the virus.

Possible Risks

Usually given as an injection in the upper arm, the flu shot contains killed flu viruses that will not cause someone to get the flu, but can cause mild side effects like soreness, redness, or swelling at the injection site. A low-grade fever and aches are also possible.

The nasal spray flu vaccine contains weakened live flu viruses, so it may cause mild flu-like symptoms, including runny nose, headache, vomiting, muscle aches, and fever. Very rarely, the flu vaccine can cause a severe allergic reaction.

When to Delay or Avoid Immunization

Certain circumstances would prevent a person from getting the flu shot. Talk to your doctor to see if a flu shot is recommended if your child falls into any of these groups:

• infants under 6 months old
• anyone who's ever had a severe reaction to a flu vaccination
• anyone with Guillain-Barré syndrome (a rare condition that affects the immune system and nerves)

In the past, it was recommended that anyone with an egg allergy talk to a doctor about whether receiving the flu vaccine was safe because it is grown inside eggs. But health experts now say that the amount of egg allergen in the vaccine is so tiny that it (but not the nasal mist) is safe even for kids with a severe egg allergy. This is especially important during a severe flu season, such as the current one, which started earlier and has been much worse than in years past.

Still, if your child has an egg allergy, he or she should get the flu shot in a doctor's office, not at a supermarket, drugstore, or other venue. And if the allergy is severe, it might need to be given in an allergist's office.

If your child is sick and has a fever, talk to your doctor about rescheduling the flu shot.

Caring for Your Child After Immunization

Pain and fever may be treated with acetaminophen or ibuprofen. Check with your doctor to see if you can give either medication and to find out the appropriate dose.

A warm, damp cloth or a heating pad at the injection site also may help minimize soreness. Moving or using the limb that has received the injection often reduces the soreness as well.

When to Call the Doctor

• Call if you aren't sure if the vaccine should be postponed or avoided.
• Call if there are serious problems after the immunization, such as an allergic reaction or high fever, or if you have other concerns.

Reviewed by: Elana Pearl Ben-Joseph, MD
Date reviewed: January 2013