000262 More Cattle Have E. Coli Than Thought

Washington - About half the cattle at the nation's feed lots carry the deadly E. coli bacteria during the summer - making it at least 10 times more common than previously thought, government research shows.

The study by Agriculture Department scientists doesn't mean that E. coli O157:H7 is any more likely to show up in the supermarket. But USDA officials, who outlined the findings Tuesday, said they are considering new controls on cattle production and beef processing.

The research “requires us to re-examine our policies and standards for dealing with this difficult organism,” Thomas Billy, administrator of USDA's Food Safety and Inspection Service, said at a conference in Arlington, Va.

The bacteria, which is most commonly found in ground beef, kills about 60 people each year and sickens an estimated 73,000 more, according to the Centers for Disease Control and Prevention.

The department's findings, which will be published in April's Proceedings of the National Academy of Sciences, are based on detection methods that are far more sensitive than previously used.

The occurrence of E. coli in feed lots drops to 1% during the winter, but scientists found that 83% of the cattle they studied had been exposed to the bacteria at some point. Calves can pick up the bacteria during the birth process, while other cattle get it from manure, scientists say. Changes in feeding methods and transportation have been shown to reduce the incidence of E. coli.

Consumer groups say the government needs to require far more extensive testing of cattle and beef to prevent people from being exposed to the germs. Testing is now required only on ground beef, a program that started after tainted hamburger killed several children in Washington state in 1993.

“Like throwing darts at a dart board, although the government hits the target occasionally, it is clearly missing a lot of the problem,” said Caroline Smith DeWaal of the Center for Science in the Public Interest.

The incidence of E. coli in cattle is believed to vary by region as well as time of the year. An industry-funded study released Tuesday found a wide variation of infection rates at packing plants. At least 18% of the cattle headed for slaughter at a dozen plants were carrying the bacteria. Two of the plants had no infected cattle, and the average rate for the 12 facilities was 3.56%.

The bacteria was found on 0.44% of the fresh carcasses sampled in the study. But no E. coli showed up once the carcasses had gone through the plants' usual cleaning process, which generally involves steam, hot water or organic acid rinses.

The study shows that E. coli testing should be done earlier in the packing process, so infected meat is caught before it is processed, industry officials said.

“It is our hope that this data will encourage USDA to re-evaluate its ground-beef sampling program,” said James H. Hodges, president of the American Meat Industry Foundation, which sponsored the research. “A carcass testing program for E. coli O157:H7 is more practicable and will help ensure that the safest and most wholesome product possible enters commerce.”

Scientists are working on additional methods of treating meat to kill a variety of pathogens, including E. coli. One is an anti-microbial agent, known as lactoferrin, that is a naturally occurring protein in the milk of mammals, including humans.

Laboratory research presented at Tuesday's USDA meeting indicated lactoferrin was effective against more than 30 different kinds of harmful bacteria, including E. coli, salmonella and campylobacter. Lactoferrin does not change the taste, flavor, color or appearance of meat and isn't harmful to humans, the researchers said.

“We have borrowed a page from Mother Nature,” said A.S. Naidu, a medical microbiologist at California State Polytechnic University-Pomona, where the treatment was developed. “We have taken a natural compound with anti-microbial properties and discovered a way to make it work on meat surfaces to provide a protective barrier against harmful bacteria.”

The government recently approved the use of irradiation to treat raw meat, but it is unclear how customers will react to that.

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