(NEW YORK) -- The U.S. Centers for Disease Control and Prevention is tracking a new strain of norovirus they say is easy to get, but hard to prevent.
The stomach bug currently making its way through the U.S. was first identified in Australia. In an average year, about 21 million Americans get the norovirus, accompanied by classic stomach flu symptoms. About 800, on average, will die from the virus, which sets in very suddenly, within hours of being exposed.
Since no one has immunity to this new strain of norovirus, ABC's Dr. Richard Besser warns that many more Americans, "perhaps 50 percent more," could fall ill.
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