Public health officials have raised to 12 the number of deaths involving listeriosis, the food-borne illness at the heart of a nation-wide recall of meat products.

According to a statement released by the Public Health Agency of Canada Monday, the latest death occurred in Ontario, where the number of deaths in which Listeria monocytogenes was the underlying or contributing cause is now 10.

One death was confirmed in Alberta on Saturday while another was recorded in British Columbia since news of the outbreak became public two weeks ago.

Another seven deaths are suspected and still under investigation, including five in Ontario, one in Quebec and one in Saskatchewan, the agency said.

A total of 38 cases across the country have now been conclusively linked to the listeria outbreak, up from 33 reported by the agency on the weekend.

The infection is of most concern to individuals who have weakened immune systems, the elderly, pregnant women and young children, the federal public health agency said in newspaper advertisements published Saturday.

Maple Leaf Foods last week expanded a recall of meat products to include everything that's processed at its Toronto plant after government lab tests conclusively linked the bacterium in the outbreak to some of the company's products.

Public health officials have warned the public to expect more confirmed or suspected cases to emerge because of the bacterium's long incubation period of up to 70 days.

NDP Leader Jack Layton blasted the federal government Monday for its handling of the outbreak, saying the Conservatives have neglected to put adequate money or resources into food safety.

He said the issue should be front and centre during the election that now appears imminent. Senior government sources on Monday said Prime Minister Stephen Harper will later this week ask the governor general to set the election date for Oct. 14.

"Absolutely it should be [a central issue] because it is affecting the health of Canadians today," Layton said.

"It represents an approach to governing our country that we've seen over the past several governments where cutbacks on the essential services, the things governments are suppose to do on behalf of Canadians, have left us vulnerable."

Federal Agriculture Minister Gerry Ritz dismissed the criticism as political posturing.

"Politicians being what they were leading into an election cycle will continue to drag the political spectre through it," Ritz said during a news conference updating the public on the state of the listeriosis outbreak.

"That's the nature of the politics of this type of situation, and it's unfortunate, but we've been focused on getting to the bottom of this, and we continue to be that focused."

Ritz noted the government has invested $113 million into food product safety and hired more frontline inspectors.

With files from the Canadian Press