Vaccine could significantly reduce human disease and associated E coli outbreaks

Ottawa, ON – January 5, 2003 – Canadian health researchers at the University of British Columbia and the University of Saskatchewan say they have developed a vaccine that significantly reduces the level of Escherichia coli 0157:H7 (E coli) in cattle.

The team’s findings are published in the December 15, 2003 online edition of the scientific journal Vaccine. The experimental vaccine was created by UBC microbiologist and bacterial diseases expert Dr Brett Finlay and Dr Andy Potter, associate director (research) at the University of Saskatchewan Vaccine & Infectious Disease Organization (VIDO). The research was supported by the Canadian Institutes of Health Research (CIHR), the Canadian Bacterial Diseases Network of Centres of Excellence, Bioniche Life Sciences, and the Beef Industry Development Fund.

“I had studied this disease for years when it suddenly occurred to me to vaccinate cows instead of children,” says Dr Finlay, UBC’s Peter Wall distinguished professor and a CIHR distinguished investigator. “There are no treatments for this disease in humans so I’m thrilled that the cattle vaccine works, and works well.”

Dr Potter worked with Dr Finlay to take the latter’s discovery of bacterial components required for E coli to colonize its host and turn it into a vaccine.

“This type of E coli doesn’t actually cause disease in cattle, but it can be deadly to humans,” says Dr Potter. “Vaccinating cattle in order to protect humans is a different twist on vaccine usage. If this vaccine is successful, it will be a significant development in the reduction of risk to humans by vaccinating animals,” he adds.

The study tested the vaccine under both experimental conditions and conditions of natural exposure. Researchers tracked E coli prevalence in 192 vaccinated and unvaccinated steers through 115 days on feed at the University of Nebraska. Vaccination reduced E coli prevalence an average of 59% compared with unvaccinated cattle. This data builds on earlier experimental tests that demonstrated decreased shedding of E coli in vaccinated cattle over the unvaccinated cattle.

While E coli prevalence varied in both vaccinated and unvaccinated steers throughout the study, it was consistently lower among vaccinated steers.

The E coli vaccine is being developed by a strategic alliance composed of UBC, the Alberta Research Council (ARC), the U of S’s VIDOand Bioniche Life Sciences, which is responsible for worldwide commercialization of the vaccine.

Clinical studies and field trials in Canada and the US are continuing to establish the efficacy of the vaccine. Currently, alliance partners are collaborating on process development activities to facilitate manufacturing scale-up of the vaccine.