Kids' Flu Shot Largely Ineffective Over Past Few Years

Schaffner noted that over the past 20 years, the match between the vaccine and the circulating flu virus has generally been good.

"In about four-fifths of the time, the experts have been pretty much on target, including the appropriate material in the vaccine. Occasionally, because the flu is fickle, it outfoxes those of us who select what's going to be in the vaccine," Schaffner said.

As for the coming flu season, the CDC in September announced that it was "optimistic" that the vaccine created this time around will be a closer match to circulating viruses.

"It's not a great vaccine, [but] it's a good vaccine. The best tool we have is the influenza vaccine -- recognizing that every once in a while, getting your influenza vaccine is not going to give you perfect protection," he said.

And any protection may be vital, according to the study in Pediatrics. In that work, researchers at the CDC analyzed data on pediatric flu deaths from the 2004-2005 season through to the 2006-2007 season.

They found that the number of kids who died of the flu over the three seasons rose from 47 and 46 in the first two years, to 73 in the 2006-2007 season. Many of the deaths were attributed to tough-to-treat staph infections. More than half of the children who died were between 5 and 17 years of age and had previously been healthy, the team noted.

The overall risk to an individual child is still very low, "but it's an important message to say even healthy children develop complications and die almost before anything much can be done for them," one vaccine specialist, the Mayo Clinic's Dr. Gregory Poland, told the Associated Press.

Schaffner stressed that vaccination is still important, but he agreed with Belshe that the nasal spray vaccine is better for children.

"The nasal spray vaccine provides broader protection against influenza virus variants than does the injectable vaccine," Schaffner said. "There are many of us who would like to see more children vaccinated and more nasal spray vaccine used. Any vaccine is better than none. Nasal spray vaccine should be used more frequently."

More information

For more about flu, visit the Centers for Disease Control and Prevention.