New study shows the elderly, overweight and obese may need a flu booster shot.
It is flu shot season and new research shows the vaccine may not work very well in people who need it the most.
New research that shows the flu shot works only about 60-percent of the time in healthy adults.
"That surely is a lot better than zero, but it's not where we need it to be in the 90+ percent range," says Dr. Michael Osterholm.
Dr. Osterholm led a review of research on the efficacy of the flu vaccine.
He says evidence for strong protection was lacking most for the elderly.
"90% of deaths from influenza occur in those over age 65. The bottom line message is that we need new and better vaccines and fast," he says.
The Centers For Disease Control recommends the flu vaccine for everyone over age six months, but even the director of the CDC's National Center for Immunization and Respiratory Disease says Osterholm's study results are consistent with what she's seen.
"I think the biggest problem is how variable influenza is. It's not one disease. We get new viruses year by year and the viruses can even change during the year, so it's been scientifically quite complicated," explains Dr. Anne Schuchat.
Complicating matters further another new study the University of North Carolina finds the flu shot may not be as potent in obese adults over the course of the flu season.
"Although the obese and overweight could make a nice antibody response initially, over time, that antibody response waned," says Dr. Melinda Beck.
There's no evidence that a second "booster" shot might help, but most public health experts agree one shot is the best shot we have to stay healthy this winter.
"Flu vaccines are definitely not perfect," admits Dr. Schuchat. "They don't work against every strain, and they don't work in everybody. But they're the best way to protect you and your family from the flu."
Instead of the regular flu shot, people over age 65 can also get a super potent flu shot called "Fluzone" high dose.
It contains four times the amount of vaccine in a regular flu shot.
The CDC hasn't officially recommended elderly people get that shot over the regular vaccine.