The outbreak was declared in the hospital's 2A medical/surgical unit on Jan. 20.

A new visitor restriction is new place for the maternal/child unit at the hospital in Cobourg.

Northumberland Hills Hospital says a 'cluster' of norovirus cases have been identified on the 2A medical/surgical unit.

The origin of the outbreak was unclear.

One-hundred-twenty-three people have fallen ill after a suspected norovirus outbreak linked to a Calgary shawarma chain, according to Alberta Health Services.

Vancouver Coastal Health says 40 staff members and 40 guests from the Sheraton Vancouver Airport Hotel in Richmond have come down with the illness.

Chicken, shellfish and raw vegetables can all carry potentially dangerous pathogens.

The stomach bug, more formally known as norovirus, is highly contagious and can't be treated with antibiotics.

The U.S. Food and Drug Administration is currently investigating whether contaminated oysters were sold south of the border.

Health officials say the number of gastrointestinal illnesses associated with raw oysters that made over a hundred people sick in three provinces appears to be dropping.