“Commonly known as the stomach flu, norovirus has been around forever, and has become the leading cause of gastroenteritis or inflammation of the intestinal tract that causes vomiting and diarrhea,” says Dr. Edmund Milder, a pediatric infectious disease specialist at Rady Children’s Hospital and UC San Diego Health.

Norovirus, often erroneously called the "stomach flu," sickens an estimated 21 million Americans and 685 million people worldwide every year, and though there is currently no preventive vaccine, a promising contender is in the works.

Norovirus is sweeping through California. The contagious stomach virus is now fueled by a new strain, accounting for nearly 70% of outbreaks. Infectious disease physician at Kaiser Permanente East Bay Jacek Skarbinski joined us on 'The Nine' with more insight on how to keep you and your family safe.

A stomach illness outbreak at the University of Guelph is part of a trend that has experts noticing a rise in stomach bugs causing vomiting and diarrhea.

Norovirus is on the rise in the United States, according to the CDC. The highly contagious virus can usually only lasts around 48 hours, South Dakota doctors say.

Norovirus cases have seen spikes in the last few weeks. We spoke with medical professionals on the virus and what it can do to the body.