Universal Flu Vaccine Soon a Reality, Scientists Say The shot could offer protection for two decades.

 -- A flu vaccine that works against all flu viruses and provides protection for at least two decades is getting closer to reality, according to scientists at Mount Sinai Health System.

The organization’s vaccine would offer better and broader and longer-lasting protection against seasonal influenza viruses as well as novel influenza viruses, Dr. Peter Palese, the chair of the department of microbiology of the Icahn School of Medicine at Mount Sinai told ABC News on Monday.

“It could potentially protect someone for a whole lifetime,” Palese said.

For example, this year’s flu vaccine was not well matched for the dominate strain of the virus currently circulating, Palese said. It is only 33 percent effective, according to the U.S. Centers for Disease Control and Prevention, because the virus “drifted” from its original form after the vaccine went into production -- a process that has to start several months before the flu season begins.

The number of people who have the flu in the U.S. is at epidemic levels, according to the CDC, with widespread activity reported in at least 43 states. With this year’s strain especially virulent, 26 children have died from flu complications so far this season. The agency is also part of another group working on a universal vaccine, a CDC spokeswoman told ABC News.

A universal shot would prevent this year’s scenario from reoccurring by targeting the part of the influenza virus that remains unchanged from year to year, explained Dr. William Schaffner, chairman of Preventive Medicine at Vanderbilt University Medical Center in Nashville.

Schaffner described the influenza virus as a sphere with “a bunch of lollipops on stems sticking out of it.” The “sucker” part of the lollipop changes from year to year but the stem parts do not, Schaffner said. The universal vaccine would attack the stem portions of the virus, theoretically protecting against all strains, he said.

“A universal vaccine is the Holy Grail and the prospects of what this could do for medicine is staggering,” Schaffner said, adding that while hopeful, questions remain about how effective such a vaccine will be.

“So far no one has been able to develop a vaccine that works against every type of flu,” said Dr. Richard Besser, ABC News chief health and medical editor. “I’d urge caution until scientists present data showing they’ve really been able to achieve this.”

Palese said the Mount Sinai team was hopeful the vaccine would work.

“We really hope it will be effective on humans -- but of course the jury is still out,” he said.

Palese said the team’s universal vaccine will go into clinical trials later this year.

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