Parental guidance: Flu shots vs. nasal mist

Q. What's the difference between the flu injection and the nasal mist? Why choose one type of vaccine over the other for my child?

A. One obvious reason to select the nasal spray is the avoidance of a needle, which can cause anxiety and pain for a child. Either option is equally safe and effective, but the nasal spray has caveats, says Tom Skinner, a spokesman for the Centers for Disease Control and Prevention in Atlanta.

"When you get a vaccine (intramuscular or nasal), you're tricking your body into believing it's being infected with a virus when it's not. Your body develops antibodies, so when you come across the real thing, you have the ability to fight off the infection," Skinner says.

The intramuscular vaccine is made with killed flu viruses. (Skinner likes to stay away from the words "shot," "injection" and "needle" because they have negative connotations.) The nasal mist is made with live but weakened virus, Skinner says. Because of that difference, a parent shouldn't choose the nasal spray if the child fits any of these categories: is younger than 2, has asthma, experiences recurring wheezing, has a weakened immune system or has long-term health problems. The nasal spray could make health problems worse, Skinner says.

With either version, the child afterward might feel like he or she has a mild case of the flu, which is one sign the immune system is responding, Skinner says. With the shot, there also can be soreness at the injection site. Parents should discuss the options with the child's pediatrician.