Five residents in the extended care unit are showing symptoms of gastrointestinal illness and two staff are showing symptoms and are off work.
The outbreak was declared Tuesday in conjunction with Niagara Region Public Health.
The main symptoms of enteric outbreaks are vomiting and/or diarrhea and the illness usually begins suddenly.
Symptoms last for 24 to 48 hours in a healthy person, but can take longer for some people.
Enteric outbreaks can spread directly from person to person, by touching contaminated surfaces, from contaminated food, and other sources.