Cattle Vaccine Could Reduce E. Coli Outbreaks
Feb. 23, 2011— -- The battle against E. coli contamination in the nation's food supply has a new weapon, but consumers are not likely to see its benefit anytime soon.
Epitopix, a Minnesota-based veterinary vaccine company, recently released a vaccine that promises to help prevent cattle from carrying E. coli O157 -- a bacteria strain that, although harmless to livestock, can be deadly to humans.
Yet critical barriers stand in the way of implementation -- the need for additional research and a high price tag.
Labeled as "E. coli Bacterial Extract," the vaccine is now available under a conditional license from the USDA, but beef industry leaders want to perform their own independent studies before moving forward with wide-scale implementation -- a common practice for newly released vaccines.
"A lot of basic research needs to occur before a technology like this is developed," said Michelle Rossman, senior director of beef safety research at the National Cattlemen's Beef Association.
At least 63,000 Americans acquire the foodborne pathogen every year after consuming contaminated foods such as ground beef or raw vegetables according to the most recent data from the Centers for Disease Control and Prevention. As a result, the CDC estimates 2,138 require hospitalization and 20 will die.
A separate CDC study found that a third of all known E. Coli outbreaks from 1998-2002 were traced back to beef products, and 35 percent were from an unknown origin.
Cargill Meat Solutions, one of the nation's largest beef producers, ran a large-scale test with the vaccine last summer on more than 85,000 animals. Initial results of the study showed promise, but the findings were ultimately thrown out.
As it turned out, that summer was an exceptional year for E. coli. The cattle carried an unusually low amount of the bacteria, even those that did not receive the vaccine. In fact, so few cattle carried the bacteria that it invalidated the entire study.
"At the end of the day, that was the deal with Cargill," said Dan Thomsen, a veterinary epidemiologist at Kansas State University who was involved with the project. "We just didn't have a challenge."
Cargill intends to repeat the study this summer for more definitive results, which could be viewed as a show of optimism in the vaccine's effectiveness.
"There were some encouraging signs, and it could turn out to be another tool in our toolbox of measures that we use to ensure food safety," said Cargill spokesman Mike Martin.
If the Cargill study can show that the vaccine works as advertised, that would create one clear signal that wider use of the product could be on the horizon. And last month, Pfizer, Inc. sent another large signal to the industry when it reached a marketing agreement with Epitopix.
David Smith, a professor of veterinary and biomedical science at the University of Nebraska-Lincoln, has been researching E. coli since 2002. The amount of interest shown by such key players in the industry could mean that wide implementation is a distinct possibility, particularly with the addition of Pfizer, he said.
"Here's a very large company that says we're willing to invest in pre-harvest interventions because we think there's a future there," Smith said.
Even so, cost could pose a problem for the industry, said Jim Sandstrom, Epitopix general manager.
