By Andrew M. Seaman
NEW YORK (Reuters Health) - Every flu season, health officials warn that people with weakened immune systems are especially vulnerable to severe flu infections, but a new study shows that more than 40 percent of flu-infected kids who die have no other chronic health problems.
The findings, from researchers at the U.S. Centers for Disease Control and Prevention (CDC), emphasize the importance of everyone who is eligible getting vaccinated against flu, experts said.
"Many people don't recognize that a healthy child could be at risk for these severe complications," Dr. Karen Wong, the study's lead author, said.
"Every child may be at risk and every child six months and older should get a flu shot this time of year," she added. Wong is a medical officer at the CDC in Atlanta.
She and her colleagues write in Pediatrics that between 54,000 and 430,000 flu-related hospitalizations and 3,000 and 49,000 deaths occur in the U.S. every year.
Since October 2004, the CDC has kept track of the number of flu-related deaths among U.S. children and teens. During that time, there were 830 flu-related deaths among people younger than 18 years old.
The average age of the children who died was seven years old, but 40 percent of the deaths occurred among children between nine and 17 years old.
"We saw newborns and teenagers," Wong said. "So any age can really be at risk."
The researchers were able to examine the medical records of 794 of the youngsters who died. Of those, 33 percent had diseases affecting the nervous system and 12 percent had genetic or chromosomal conditions that are known to dispose people to severe reactions when they're infected by the flu.
But another 43 percent had no chronic medical conditions that would put them at high risk for complications.
"It's actually not possible to tell from this study why these previously healthy children had such a severe outcome," Wong said. "But one thing I think this study can tell us is that most children in this study did die very quickly."
On average, otherwise healthy children were more likely to die of the flu within three days of the first symptoms and before they were even admitted to a hospital.
It's not yet possible to sort out which healthy children may or may not have a severe reaction to the flu, Dr. Jon Abramson said. He's chair of the Department of Pediatrics at Wake Forest Baptist Health in Winston-Salem, North Carolina.
"It does appear to be some genetic factor that makes you at higher risk," Abramson, who wasn't involved in the new study, said.
About 40 percent of all the children who died also had a bacterial infection in addition to the flu, often in the form of pneumonia.
Also, the researchers found that only a small number of the children and teens had received their flu shots. Among the healthy kids who died, just 9 percent had had a vaccine.
In comparison, 22 percent of high-risk kids had been fully vaccinated.
With few exceptions, the CDC recommends that everyone six months old and older be vaccinated against the flu.
This year, a new four-strain vaccine is approved for kids but expected to be in limited supply. Experts say if only the usual three-strain version is readily available, it's more important to get children vaccinated as soon as possible rather than waiting for the new vaccine (see Reuters Health story of September 3, 2013, here:).
"Don't take (the) chance that your child - because they're healthy - is not going to get hospitalized or die because of the flu," Abramson said.
He added that pregnant women should get the flu shot to protect themselves as well as their newborns.
"Children who are younger than six months old are too young to be vaccinated," Wong said. "Vaccinating the pregnant mom is recommended so some of that protection can be passed onto that newborn."
Abramson also said that children who are experiencing breathing problems or confusion should be taken to the hospital.
"The best way to protect your family is to get a flu vaccine every year," Wong said, adding that people can find additional information on the CDC's website (cdc.gov/flu).
SOURCE: http://bit.ly/16GStY3 Pediatrics, online October 28, 2013.