Health officials: As flu virus changes, so must vaccine to combat it
ATLANTA (AP) -- With new versions of bird flu emerging, U.S. health officials announced Monday that scientists must stir up a different vaccine recipe to try to protect people.
That's not unexpected because flu viruses -- whether in birds or people -- are constantly changing. Federal health officials are merely trying "to keep right on the virus's tail and keep our vaccines as up to date as much as we can," said Dr. William Schaffner, a Vanderbilt University vaccine expert.
But despite its mutations, the continent-hopping bird flu virus seems content slaying wild birds and farm chickens, causing an estimated $10 billion in global agricultural losses.
It still doesn't easily infect people. That's good news, right? Not necessarily, said Schaffner, who suggested three possible scenarios.
The virus could continue to spread in its current forms, mostly sparing humans. It could mutate into a more harmless version, which isn't even dangerous to birds. Or it could become a deadly human flu that spreads easily around the globe with the potential to kill millions, he said.
"We cannot let our guard down, because a series of genetic changes could happen at any time that could allow this virus to pick up the capacity to move from person to person," Schaffner said.
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