Several Silk plant-based milks affected by a nationwide recall are gradually coming back to shelves amid a listeria outbreak that has killed three people in Canada, though the number of those sickened and killed has continued to grow as officials track the matter.

A specific production line at a factory in Pickering, Ont., that the contamination was traced to was shut down last month and remains closed as authorities inspect it, but other facilities are increasing production, Danone Canada, the manufacturer of Silk beverages, told Global News on Thursday.

“We have progressively ramped up production of our Silk refrigerated products in other facilities and products impacted by the recall are gradually coming back to shelves,” Jennifer Vincent, a spokesperson for Danone Canada, said in an email.

The company has also ramped up testing, she said.

“Out of an abundance of caution, we have proactively increased the frequency and number of tests in all Silk refrigerated products production and warehousing facilities.”

The Canadian Food Inspection Agency is continuing its investigation into the listeria outbreak linked to the recalled plant-based milks sold by Silk and Walmart’s Great Value brand.

At least 20 people have been reported sick with listeriosis – the illness caused by listeria bacteria – in Ontario, Quebec, Alberta and Nova Scotia. Out of these cases, 15 people have been hospitalized. Three have also died in Ontario.

The illnesses occurred between August 2023 and mid-July 2024, according to the Public Health Agency of Canada.

The CFIA issued the recall on July 8 for 15 types of almond, coconut, oat and cashew milks sold by Silk as well as three of Great Value brand’s almond milks.

Last week, the agency said that “all affected products were made on a dedicated production line, which has been completely disassembled while inspection at the facility is ongoing,” and that the facility was a packaging one in Pickering.

“No production on this dedicated production line will restart until the necessary corrective measures are implemented and the CFIA is satisfied that any contamination has been identified and eliminated,” the agency said.

Danone’s Vincent said no Silk products have been produced at or shipped from the impacted Pickering facility since July 6.

She said the company was “actively investigating” the cause of the contamination with the CFIA and its third-party manufacturer.

“This is a rigorous process that takes time, but it is important that we get to the bottom of this,” Vincent said.

Two class-action lawsuits have been filed in British Columbia and Quebec against Danone and Walmart Canada over the listeria outbreak linked to the recalled plant-based milks.

Listeria is a type of bacteria commonly found in soil and causes food-borne illnesses in humans.

Food contaminated with listeria may not look or smell spoiled but can still make you sick, the CFIA says.

Typical symptoms associated with listeriosis include gastrointestinal problems — like diarrhea, abdominal cramps, nausea and vomiting — as well as fever, muscle aches, neck stiffness and severe headache. In serious cases, it can even cause death.

Good sanitation practices can help prevent listeria illness, experts say.