Viruses are fascinating. A 27nm particle first isolated in 1978 from the poop of ill students and teachers at a Norwalk, Ohio school causes millions of illnesses a year by using a host’s cells to make more viruses.

And spread them to other hosts through projectile vomit and explosive diarrhea.

Sort of like what’s happening in Corunna, Michigan where 30 patrons of an Applebee’s are, according to MLive, sick with noro symptoms.

The Shiawassee County Health Department confirmed the virus was responsible after a person became ill during the investigation period of March 9-12. The transmission source has not yet been identified.

“As of start of business day on March 22, 2016, a total of thirty people experienced similar symptoms and have contacted the Shiawassee County Health Department,” reads a statement from the health department’s Personal Health Services Division.

A call for comment from the restaurant was not immediately returned.

Nicole Greenway, director of personal community health for the Shiawassee County Health Department, said the restaurant is cooperating with the investigation and has fully sanitized the kitchen, bathroom and customer dining areas.

“We were notified by a person from the state who’d seen a complaint and we followed up on that,” she said, of the March 14 notification.

“Unfortunately it goes around, it’s very contagious,” said Greenway, referencing a recent norovirus outbreak at the University of Michigan that led to more than 100 people getting ill. “You can get it from touching a door handle or something like that. One public health message is to watch your hands. That’s a good prevention (tip).”