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It's one specific strain of E. Coli in the tainted spinach: E. Coli 0157 H7. Even though it's not clear how it got in the spinach, one possible source is cattle waste. It could have come from contaminated irrigation water used to grow the spinach. Researchers say they're closing in on a new approach to protecting the public from E. Coli with a vaccine given to cattle instead of humans.
From Nebraska Public Radio, Sarah McCammon reports.
SARAH MCCAMMON: Past outbreaks of E. Coli related illnesses have come from tainted beef, which can become contaminated during processing. Cattle can tolerate the bacteria with no problems, but in humans this type of E. Coli can cause severe illness or even death.
At a University of Nebraska research feed lot near Lincoln, several hundred cattle are part of a clinical trial aimed at fine tuning a Canadian vaccine for E. Coli: 0157. A team of mostly graduate students works on the messy job of collecting samples of the animals' blood and manure.
Feedlot specialist Galen Ericson explains how the process works.
Mr. GALEN ERICSON (University of Nebraska): We've run them through what they call a crowd shoot where the cattle actually come in in a group of eight to ten.
MCCAMMON: The trials began in 2002 and researchers have since tested some 25,000 head of cattle from across Nebraska. Results of earlier tests were published in the journal Vaccine in 2004.
Epidemiologist David Smith says the vaccine reduces the number of animals with E. coli bacteria in their manure by 60 percent to 70 percent. Coupled with what people in the industry call interventions, safety practices like washing hides and carcasses after slaughter, Smith says the vaccine could significantly reduce the risk of contamination to the food supply.
Dr. DAVID SMITH (Epidemiologist): There may still be organisms coming into the plant - we're not eliminating it - but at a much lower level so that the interventions that take place post-harvest have an opportunity to be effective. They don't get overwhelmed.
MCCAMMON: Back in Lincoln at a university laboratory, technicians prepare manure samples for analysis. Veterinary science professor Rod Moxley says they use a technique that helps them hone in on E. coli: 0157.
Dr. ROD MOXLEY (University of Nebraska): There are nutrients in there to make the bacteria grow. There's also other substances in there that are selective for the bacteria. They will kill out competing organisms.
MCCAMMON: Funding for the research comes from several sources, including the U.S. Department of Agriculture, the cattle industry and the Ontario-based biotechnology company Bioniche Life Sciences.
President and CEO Graeme McRae says so far the company has invested roughly $15 million in research and development and will spend at least $50 million more to get the product on the market. But McRae says he believes the E. coli vaccine will catch on with the industry and turn a profit in three to four years.
Mr. GRAEME MCRAE (Bioniche Life Sciences): One feedlot called and said we process a million animals at a time. You know, how are you going to have enough vaccine for us to put it in the system?
MCCAMMON: McRae says the treatment likely will cost $6 to $8 per animal. He says he hopes to see every herd of cattle in North America receive the vaccine.
But animal science professor Terry Klopfenstein, a member of the Nebraska research team, says turning the vaccine into a viable product for producers may be a challenge, at least at first.
Dr. TERRY KLOPFENSTEIN (University of Nebraska): For them, what's the economic benefit to vaccinating their cattle? There is no direct benefit because the cattle will not gain faster. They'll not do it more efficiently. The meat won't taste any better.
MCCAMMON: Still, Klopfenstein says he thinks the vaccine would ultimately benefit producers by making beef safer and helping shore up public confidence in the industry.
Dr. KLOPFENSTEIN: It's of benefit to the industry to be reducing the risk of either the meat or where that manure may end up.
MCCAMMON: Researchers expect to finish their current trial this fall and complete their analysis of the data by the end of the year. Officials with Bioniche say the company is hoping to see the E. coli vaccine approved for use in North American cattle as soon as next year.
For NPR News, I'm Sarah McCammon in Lincoln, Nebraska.
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