Find out why and when your child needs the flu vaccine.


Why does my kid need the flu vaccine?

The flu vaccine protects against the flu (influenza), which is a very contagious infection of the respiratory system. Flu germs spread through the air (from coughing, sneezing, etc.) and from contact with infected objects and surfaces. The flu can make your child feel very achy and tired, causing fever, chills, loss of appetite, coughing, runny nose, and sore throat.

Though the flu is common, it can be uncomfortable and dangerous, especially for young kids. The flu can lead to complications like pneumonia, staph and ear infections, and fevers that may cause seizures. Though some parents might consider the flu a more serious cold, the virus sends more than 20,000 children under 5 to the hospital each year; children under 2 face the most serious risk.

Because complications from the flu can be so serious, the American Academy of Pediatrics (AAP) and the Centers for Disease Control and Prevention (CDC) now recommends that children ages 6 months through 19 years receive the flu vaccine annually, as well as parents, caregivers, and anyone else who has close contact with kids . The vaccine is also very important for pregnant women.

The flu vaccine is especially recommended for kids and adults who are at higher risk from getting very sick should they contract the flu, including:

  • Children aged 6 months up to their 19th birthday
  • People who live in nursing homes and other long-term care facilities
  • Pregnant women
  • People who live with or care for those at high risk for complications from flu, including: - Health care workers - Household contacts of persons at high risk for complications from the flu - Household contacts and out of home caregivers of children less than 6 months of age (these children are too young to be vaccinated)
  • People 50 years old and older
  • People of any age with certain chronic medial conditions

What's the recommended flu vaccine schedule?

In most cases, the flu vaccine is received once each year. Children over 6 months should have flu shots in September (or as soon as flu vaccine is available) or any time in the influenza season -- into December, January, and beyond. Flu viruses change every year, which means that new vaccines are needed each year to protect against current strains. Even if you or your child received a flu vaccine in a previous year, you both still need to get revaccinated to develop immunity to the current year's strain.

If your child is under age 9 and receiving the flu shot or nasal spray vaccine for the first time, it's recommended that he get two doses at least four weeks apart. "This is the best way to build up immunities that first year," says Neal Halsey, MD, director of the Institute for Vaccine Safety at the Johns Hopkins Bloomberg School of Public Health in Maryland a member of the Parents magazine board of advisors. But only one dose is needed in subsequent years.

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.

Is there mercury in the flu vaccine? Should I be concerned?

While mercury-free brands of the flu vaccine are available, the majority of flu shots still contain some thimerosal, a mercury-based preservative that used to be found in a number of vaccines -- and that some people have claimed may cause autism.

However, more and more evidence -- via larger, better-designed studies -- has failed to find any link that thimerosal in vaccines is responsible for the onset of autism in babies and children. Most recently, a study published in the Archives of General Psychiatry found that cases of autism in California continued to increase every year from 1995 to 2007, despite the fact that thimerosal was removed from most vaccines by 2001. Experts believe that if thimerosal were responsible for autism, cases would have dropped significantly after that time.

If you're concerned, more and more versions of thimerosal-free flu shots are available each year, and many pediatricians currently offer them. And children older than 2 can receive the nasal spray form of the vaccine, which does not contain thimerosal either.

Who shouldn't get the flu vaccine?

While the flu vaccine is one of the Centers for Disease Control and Prevention's recommended childhood vaccinations, people who fall into the following categories should not receive it:

  1. Babies under 6 months
  2. Kids who've had an allergic reaction to the flu vaccine in the past
  3. Kids who are severely allergic to eggs (since the vaccine is grown in chicken eggs, traces of egg protein may be present)
  4. Those with a history of Guillain-Barre syndrome (GBS), a nervous system disorder
  5. Kids who are moderately or severely ill (more than just a cold, for example) should wait to get vaccinated

Furthermore, the nasal spray should be avoided by the following groups:

  • Kids younger than 2 and adults 50 and older
  • Kids with asthma or other respiratory problems
  • Kids with long-term health problems including diabetes, kidney disease, heart disease, or lung disease
  • Pregnant women

Talk to your doctor if you're concerned about whether or not the flu vaccine is safe for your child.

Are there any side effects from the flu vaccine?

The most common side effect from the flu shot is soreness, redness, or swelling near the shot site. Babies and children may develop a fever and feel a bit achy or fussy for a few days after receiving the vaccine.

Children who receive the nasal spray vaccine may experience a runny nose or congestion, as well as cough, chills, fatigue, sore throat, or a slight headache.

As with any vaccine, severe allergic reactions are very rare, but possible. If you notice your child having difficulty breathing, hoarseness or wheezing, hives, paleness, weakness, dizziness, or a rapid heartbeat shortly after receiving the vaccine, call your doctor right away.

Is the flu vaccine really necessary?

Even though death from the flu is rare, serious complications in young children are not. That's why the American Academy of Pediatrics, the Centers for Disease Control and Prevention and most doctors recommend that babies, young kids, and children with certain chronic health conditions get vaccinated every year.

"We've seen an increasing link between the flu and serious bacterial pneumonia, as well as other serious bacterial infections," says Neal Halsey, MD, director of the Institute for Vaccine Safety at the Johns Hopkins University Bloomberg School of Public Health in Maryland and Parents magazine advisor. "And it's just not possible to predict which children may develop complications from the flu."

Because the vaccine is designed to protect against the main strains of flu that are expected to circulate that year, its effectiveness depends on how close the vaccine matches what circulates, says Dr. Halsey. "The vaccine is between 70 and 90 percent effective in most years, so there's still a pretty good chance your child will be protected from the flu, even if that year's vaccine isn't a perfect match."

Sources: Michael T. Brady, MD, the Vice Chair of the AAP's Committee on Infectious Diseases. Neal Halsey, MD, director of the Institute for Vaccine Safety at the Johns Hopkins University Bloomberg School of Public Health in Maryland and a member of the Parents magazine board of advisors. Paul Offit, MD, Chief of Infectious Diseases at the Children's Hospital of Philadelphia in Pennsylvania and a member of the American Baby magazine advisory board member. Robert W. Sears, MD, author of The Vaccine Book: Making the Right Decision for Your Child. Continuing Increases in Autism Reported to California's Developmental Services System from Archives of General Psychiatry, Vol. 65 No. 1, January 2008. CDC sections on Flu, Flu Vaccination, and Thimerosal. FDA section on Thimerosal in Vaccines. American Academy of Family Physicians section on Preventing the Flu. Mayo Clinic section on Flu Vaccination.

Copyright © 2008;

Updated October 2009

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