Deadly E. Coli Bug May Affect Half of U.S. Cattle
Wednesday, November 10, 1999
By Julie Vorman
WASHINGTON (Reuters) - A deadly strain of E. coli bacteria
is far more common in U.S. cattle than previously thought, and
may be found in half the animals that are made into ground beef,
steaks and other cuts, a senior U.S. Agriculture Department
official told Reuters on Wednesday.
The surprisingly high rate of E. coli 0157:H7, detected by
more sensitive testing techniques used since September, has
prompted the USDA to take the unusual step of re-evaluating how
it regulates the foodborne disease.
The bacteria can cause kidney failure and death among
children or the elderly who eat contaminated ground beef.
But among cattle, E. coli 0157:H7 lives harmlessly in the
digestive tract. The bug migrates when animals are slaughtered
and skinned, moving from internal organs and hides to flesh.
Tom Billy, administrator of the USDA's Food Safety and
Inspection Service, said in an interview that agency scientists
were still analyzing data but decided to alert the industry
about the unexpected preliminary results.
USDA regulations to protect consumers from E. coli 0157:H7
contamination were based on 1994 data showing the bug occurred
in one of every 2,000 or so carcasses at the slaughter plant.
``The prevalence could be much more common and as high as
one in every two carcasses,'' Billy said. ``If that's true, it
changes significantly the options available to us to achieve the
zero tolerance.''
USDA regulations allow ``zero tolerance'' of E. coli
0157:H7. If tests detect the pathogen in raw ground beef, that
batch is considered adulterated and is usually destroyed.
Companies can process the meat at high temperatures to kill the
bacteria, then use it in cooked foods such as canned chili.
``We are not changing the zero tolerance policy. That will
remain in effect. That will not change,'' he said.
The USDA is drafting some options that may include changes
in testing procedures, and will publish them next month. A
public hearing will be held in mid-January, Billy said.
The new data was criticized as misleading by cattlemen.
``There is no evidence the prevalence of this organism has
changed at all since we began studying it in the early 1990s,''
said Gary Weber of the National Cattlemens Beef Association.
The USDA data reflects only whether cattle have been exposed
to the bug at some point in their lives -- not that they are
carrying it at the time of slaughter, Weber said. Actual
infection rates are less than one-half percent of cows, based on
testing by meat grinders and processors, he said.
The new data also raises the issue of whether farmers and
ranchers need to do more to prevent E. coli in their herds.
The bacteria is found more often on the hides of feedlot
cattle, the USDA said. Feedlot cattle are typically fattened in
a confined area just before going to slaughter.
The animals spread E. coli 0157:H7 by defecating and
drooling in shared water troughs.
Consumer groups say on-farm prevention is essential.
``We'd like to see development of some kind of vaccine or
competitive exclusion product for cattle that will eliminate
this strain of bacteria from the gut of the animals,'' said
Caroline Smith DeWaal, a food safety expert with the Center for
Science in the Public Interest.
The U.S. meat industry is also examining the issue.
The American Meat Institute, an industry trade group, has
funded research to measure how much E. coli is left on an animal
hide after slaughter. The researchers are also trying to
determine whether various chemical dips, steam vacuuming or
other treatments of hides are best to kill the bacteria.
With E. coli more common in raw meat, processors are likely
to embrace irradiation technology that can kill the bacteria.
``Several companies are looking very hard at irradiation
right now,'' said Mike Doyle, a University of Georgia
researcher. ``The economics are an important factor. How much
are we willing to pay for ground beef, and how much are we
willing to throw out as adulterated?''
The USDA's long-delayed regulations for irradiation use in
plants will be issued by the end of December, Billy said.
The USDA monitors E. coli 0157:H7 in ground beef by taking
8,000 samples annually at slaughter plants and grocery stores.
A recent outbreak of the bug at a New York fair killed an
elderly man and a three-year-old girl, and sickened more than
600 others. Investigators have theorized a water well may have
been contaminated by nearby dairy cow barns.
Nationwide, an estimated 52 Americans die annually from E.
coli 0157:H7 and 60,000 others fall ill from the bug.
^REUTERS@
