Norovirus is on the rise. Here's what norovirus feels like, some common causes of the latest outbreak, how long symptoms can last and more crucial info.

“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.

Despite millions of cases of norovirus in the U.S. each year—and a current surge in outbreaks—there is still no vaccine for the stomach bug. Here's why it's taking so long, and how close we are to a norovirus vaccine.

Recovering from norovirus gives the body a certain level of protection for some time. But it's important to know if it's possible to get infected again.