Health officials say 29 Minnesotans recently suffered from norovirus after eating oysters at a restaurant, CBS Minnesota reports.

They fell ill after eating the raw oysters at Travail Kitchen in Robbinsdale on March 20. The restaurant notified public health authorities and has since stopped serving the oysters, according to officials.

The Stellar Bay Gold oysters had originated from Deep Bay 14-8 in British Columbia, and were harvested on March 10. Public health agencies are encouraging people to check shellstock tags and discard oysters from the particular harvest.

Norovirus symptoms include nausea, vomiting and diarrhea. The Minnesota Department of Health says there is high norovirus activity in the state, and most of the cases are connected to the oysters.

“People with norovirus can spread it to others even after symptoms stop,” said MDH Epidemiologist Supervisor Senior Carlota Medus.

To mitigate the spread, health experts say to wash your hands after using the bathroom, and before preparing food for others.