A sandwich shop inside the Princess Margaret Cancer Centre has been linked to at least three cases of Listeria infection.

Toronto Public Health says that a Druxy's restaurant inside the University Avenue hospital has been shut down after three cases of the foodborne illness were confirmed among people who have dined there.

The cases, two of which were confirmed on Wednesday, are believed to have resulted from visits to the restaurant between Jan. 1 and March 12.

“We know that Listeria is commonly spread from deli meats, soft cheeses and unpasteurized milk so deli meats is the first place we are looking at in a restaurant like Druxy’s,” Associate Medical Officer of Health Dr. Vinita Dubey told CP24 on Wednesday. “We have done extensive testing and do have some indication that some of the foods may have been the source. But our investigation is ongoing.”

Some of the common symptoms of listeriosis – the illness caused by Listeria infection – include a fever, diarrhea, vomiting, nausea and cramps but more serious symptoms such as seizures, severe headaches and loss of balance can develop among those with a weak immune system, which would be of particular concern given the restaurant’s location in the Princess Margaret Cancer Centre.

Druxy’s owner Peter Druxerman told CP24 that he voluntarily made the decision to close the restaurant after being alerted to the first case of listeriosis on March 13.

He said that the person who fell ill may have contracted the virus as a result of contamination involving a slicer used to cut sandwich meats.

“We decided at that point that the best route would be for us to close the restaurant and make sure that it was fully safe for all customers and do a thorough cleaning and through inspection with the assistance of an independent health inspection agency and also a third-party cleaner,” he told CP24. “The restaurant won’t be open until the health department and Druxy’s are satisfied that it is fully safe for the customers to eat there.”

Druxerman said that a third-party health inspection agency has given Druxy’s the green light to reopen and Toronto Public Health will now complete its own inspection.

He said that while some customers could be scared off from Druxy’s following the outbreak, there is a risk to every restaurant.

“We are humans. We do our best to clean and we have procedures that are far in excess of what the health department demands or expects,” he said. “We have a private inspection agency that comes in four times a year to each store. They do swabs so we are sure of what is going on and we follow up and take it very seriously.”

Dubey said that Druxy’s has been “extremely cooperative” so far and could reopen soon, though no timeline has been provided.

She said that there have been “deep cleanings” conducted as well as “extensive environmental testing” to ensure that anything that was contaminated with Listeria is no longer present.

Meanwhile, anyone who has eaten at the sandwich shop in recent months is being urged to visit a doctor if they experience any symptoms.

“We are asking individuals who may have eaten at this restaurant from Jan. 1 onwards to watch for symptoms and if they get symptoms to see their doctor and get tested,” Dubey said.