Canadian researchers have developed a vaccine that they say will keep deadly E. coli bacteria out of our food and water supplies.

The vaccine works by dramatically reducing the amount of E. coli shed by cattle in their manure, says Dr. Lorne Babiuk, who helped develop the vaccine with a team from the University of British Columbia, the University of Saskatchewan and the Alberta Research Council.

"For example, in a normal animal, they might excrete 1 million bacteria per gram of manure," Babiuk explained to Canada AM. "After they're vaccinated, they excrete maybe 1,000.

"So, that's a reduction of a thousandfold, which clearly reduces the amount of contamination of the environment."

The vaccine specifically targets E. coli 0157:H7, the strain that killed seven people in Walkerton, Ont., and that was most recently linked to tainted spinach in the United States.

Meat and poultry can become contaminated with the bacterium during slaughter by contact with small amounts of intestinal content or feces. And produce and water sources can be contaminated from E, coli-laced runoff.

E. coli doesn't make cattle sick. But when humans eat food or water contaminated with the bacteria, they can develop bloody diarrhea, severe cramps and potentially fatal kidney failure.

"What is new about this is that normally, we vaccinate cattle to protect cattle against cattle diseases, and we vaccinate humans to protect humans against human infection. But here, we're vaccinating an animal to protect a human from an infection," says Babiuk.

Babiuk believes that cattle farmers will begin vaccinating their herds, not to protect the health of their cows, but because consumers will demand it.

"The companies that are going to buy the meat will probably require or request that they be vaccinated to reduce the contamination," he says.

"Or the supermarket may actually say we want to have all of our beef from vaccinated animals."

Graeme McRae, the CEO of Bioniche Life Sciences Inc. which is producing the vaccine, believes Canada is the first country to approve such a product.

"This is a major breakthrough in terms of controlling a disease that appeared to me uncontrollable," says McRae.

Canada is the first country to approve such a product and McRae says the company is already getting requests from Canadian cattle producers for the vaccine. But it's not available quite yet.

The vaccine was given preliminary approval by the Canadian Food Inspection Agency two weeks ago, allowing Bioniche to sell the vaccine to Canadian veterinarians, while they provide additional test information to the inspection agency.

Babiuk says that if all goes well with the final tests, the vaccine could be on the market in about 18 months.

What's more, his team is hoping to use their research to develop similar vaccines to prevent salmonella and Campylobacter in poultry.