There's now been a fourth case of E. coli infection in Quebec.

That brings the number to 15 confirmed cases across Canada in the last few weeks, thought to be linked to beef coming out of the XL Foods plant in Alberta.

The plant has been at the centre of what is now the largest beef recall in Canadian history.

On Thursday, the plant resumed limited activities under the supervision of the Canadian Food Inspection Agency, but the all-clear has yet to be given for beef to actually leave the facility.

For more information on the beef recall, visit the Canadian Food Inspection Agency's page here.