What's the difference between the flu shot and the nasal spray vaccines?
Aside from how the vaccine is administered (an injection in the arm vs. a squirt up the nose), there are some other key differences between the flu shot and nasal spray.
- The flu shot can be used by more people. The shot is approved for use in anyone over 6 months old, including pregnant women and people with chronic health conditions, while the spray is not approved for babies under age 2 (or people over age 49), pregnant women, or those with certain chronic medical conditions or suppressed immune systems.
- The flu spray may protect against more flu strains. "There's some evidence that the nasal spray provides enhanced cross-protection against viruses not included in the vaccine," says Michael T. Brady, MD, vice chair of the AAP's Committee on Infectious Diseases. "This means that if the flu strains in the vaccine happen to differ from the circulating strains in a given year, the nasal vaccine provides better odds at protecting those non-covered strains than the shot does."
- The potential side effects are different. Children who receive the spray may develop a runny nose or congestion, as well as a cough, chills, fatigue, sore throat, or a slight headache. Children who get the shot might have muscle aches and soreness near the injection site.
- The flu spray contains live (but weakened) viruses, while the shot contains inactivated (dead) viruses. Neither should make your child come down with the flu, but in rare cases, those who've received the nasal spray can pass the viruses on to others.
- Some brands of the flu shot contain the mercury-based preservative thimerosal. The spray is thimerosal-free.
"Both versions of vaccine are safe and effective," says Dr. Brady. "But I'd recommend the nasal spray for children who can receive it -- most healthy kids over age 2. It may be slightly more effective, and it also means one less shot for your child."
Talk with your doctor to determine which version of the vaccine might be best for your child.