The flu vaccine isn’t just for the elderly and infirm. It’s for babies, kids and adolescents, too.

The vaccine can protect them from what sometimes can be a devastating infection. Because toddlers and preschoolers are a key way that flu spreads throughout communities, protecting little ones may be one of the best ways to protect everyone.

The flu, a highly contagious respiratory disease caused by a virus, strikes 5 to 20 percent of the U.S. population and kills about 36,000 Americans a year. Flu complications cause about 20,000 young children a year to be hospitalized and killed 86 children in the 2007-08 season, according to the Centers for Disease Control and Prevention (CDC). Peak flu season is usually between December and March. So although the vaccine has been available since September, it’s certainly not too late to protect your family now.

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For the first time, experts are calling for all children ages 6 months to 18 years to get the vaccine. It’s also recommended for pregnant women and anyone who lives with or spends time around children. A pregnant woman who gets the vaccine can protect her infant, and in fact, it is recommended that all eligible and high-risk family members should get vaccinated before bringing a new baby home.

Children under 9 years getting the flu vaccine for the first time need two doses a month apart. Older kids and adults need only one dose a year. There are two types of vaccines: The traditional flu shot is given in the arm or thigh to people older than 6 months, including pregnant women. The nasal spray is approved for most healthy people ages 2 to 49 years, but should not be used for pregnant women.

Issues and answers

Some parents have concerns about giving their kids the flu vaccine. Here’s a look at the issues and what experts have to say:

• Side effects. Research has found few side effects in kids given the flu vaccine. However, about 10 to 35 percent of children under 2 years experience fever afterward, according to the American Academy of Pediatrics (AAP), which recommends the vaccine. It’s not possible to contract the flu from the flu shot, which contains dead viruses. In clinical studies of the nasal vaccination, which contains weakened viruses, people have spread the vaccine viruses to close contacts in only a few rare cases.
  
  
• Preservative. Thimerosal, a mercury-based preservative still found in some flu vaccines, is believed by some parents and Web groups to have a causal relationship to the onset of autism. However, major scientific studies have found no evidence to support a link between autism and vaccines that contain thimerosal, according to the CDC. The AAP notes that the nasal spray and some types of the shot (single-dose Fluzone, Fluvirin for people ages 4 and up) have no thimerosal. If you are concerned about thimerosal, you may want to ask your pediatrician about these options.
  
  
• Effectiveness. In some years, the flu vaccine provides little protection because health officials and vaccine manufacturers have to choose months in advance which three flu strains to combat and don’t always get a good match with next year’s influenza virus strains. And some experts say the flu shot doesn’t work nearly as well in children as the nasal spray. Even with these caveats, the flu vaccine remains one of our few weapons against the flu. “We may not have a perfect influenza vaccine, but we have a darn good one,” said William Schaffner, M.D., president-elect of the National Foundation for Infectious Diseases.
  

The vaccine is also recommended for people age 50 and older, people with chronic diseases, extended-care residents and healthcare workers. Is there anyone who shouldn’t get vaccinated? Only infants younger than 6 months and people who have had a severe reaction to the flu vaccine, have a severe allergy to chicken eggs (viruses for the vaccine are grown in eggs), developed Guillain-Barre syndrome within six weeks of getting the flu vaccine or currently have a moderate to severe illness with fever.

More: Find out other ways to prevent colds and flu.

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