Norovirus Spreading in U.S.

While we worry about the flu, another virus that can get us quite ill is creeping up on us. It is called norovirus, and it started in Sydney, Australia, late in 2012.

It has spread from Australia through England and Wales, and now to the U.S.

"It's a new strain of norovirus," CDC Dr. Richard Besser said. "Norovirus is the leading cause of diarrheal illness in the U.S. Every year 21 million people get this and 800 people die from this. It is spreading like wildfire."

It's not clear whether this strain is more likely to infect people or make them more ill than previous strains, but according to the CDC’s division of viral diseases, any time a new strain emerges, it has the potential to increase disease, because people have not been exposed to it before, so they're more susceptible.

The norovirus season typically runs from November through March and peaks in January.