On top of the common flu, there is now a new threat.  A nasty strain of norovirus, commonly known as stomach flu, is spreading across the nation.

Each year, more than 20 million Americans catch the bug.  The Centers for Disease Control report this new strain, which originated in Sydney, Australia is responsible for 140 outbreaks of the virus thus far.

Norovirus is very contagious and you can pick it up by touching almost any surface.  And unlike the seasonal flu, you can contract the bug from food and people who prepare your food.

"The symptoms you get normally come on suddenly, usually severe," said Dr. Kavita Sinha, a Palm Desert internist.  "You can have a low-grade fever, followed by diarrhea and vomiting that's usually pretty debilitating."

There's no vaccine for norovirus and no drug to treat it.  The good news, in most cases, the virus runs its course in three to four days.