Published Date: 2005-06-28 23:50:00
Subject: PRO/AH/EDR> BSE, bovine - USA (08)
Archive Number: 20050628.1826
BSE, BOVINE - USA (08)
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
In this report:
 BSE - USA: testing changes
 BSE - USA: OIE report
 BSE - Canada: testing update
Date: 25 Jun 2005 4:46 PM
From: Mary Marshal<email@example.com>
Source: New York Times [edited]
Testing Changes Ordered After U.S. Mad Cow Case
Substantial changes in the nation's mad cow testing system were
ordered yesterday after British tests on a cow slaughtered in
November 2004 confirmed that it had the disease even though the
American "gold standard" test said it did not.
"The protocol we developed just a few years ago to conduct the tests
might not be the best option today," Agriculture Secretary Mike
Johanns said in making the announcement. "Science is ever evolving."
At an afternoon news conference in Washington, Mr. Johanns described
serious errors in the testing in the United States on the animal, the
2nd one found with mad cow disease, formally known as bovine
spongiform encephalopathy. But he also defended the safety of
American beef, reminding reporters that the animal had been
incinerated rather than being ground into hamburger, as the 1st one
was in late 2003.
The head of the testing laboratory in Weybridge, England, who joined
the news conference by telephone, said he was "pretty confident" that
the incidence of mad cow disease in American herds was "very little
indeed." Of 388 000 tests in the last year, only 3 positive rapid
tests have been found, and only this one has been confirmed.
Until yesterday, the Agriculture Department used a rapid test called
an Elisa [ELISA, enzyme-linked immunosorbent assay] and confirmed any
positives with a slower immunohistochemistry test, which it calls the
The Europeans and the Japanese use those tests, but routinely add a
confirmatory western blot test, which is more sensitive. The
Agriculture Department asked the English laboratory, regarded as one
of the world's best, to retest the samples.
In response to questions, Dr. John Clifford, the Agriculture
Department's chief veterinarian, revealed another surprise: the
animal's disease strain did not closely resemble the British-style
strain found in the 1st mad cow, which was born in Canada and raised
in Washington State. Instead, it was closer to a strain found in
France -- a result, another scientist said, that suggested that the
infection had come from a different pool of infected feed, possibly
imported from France.
Mr. Johanns refused to give details about the animal, other than to
repeat that it was born before the 1997 ban on feeding ruminant
protein to ruminants, that it was raised for beef, not dairy, and
that it was too crippled to walk when it was killed. There was "no
evidence" that it was born outside the United States, Mr. Johanns
said, and its brain was sampled for tests at a plant specializing in
diseased and dead animals. Most beef animals are slaughtered when
they are less than 3 years old.
DNA tests will be started to find the herd it was raised with, Mr.
Johanns said. Normally, an infected animal's whole herd is
slaughtered on the assumption that all ate the same feed.
He described several errors in the testing process in the United States:
(1) The brain samples were frozen, which makes some tests harder. (2)
Parts from 5 carcasses were temporarily mixed up. (3) No written
records were kept.
Also, after the animal tested positive on 2 rapid ELISA tests and
then negative on the slower, "gold standard" test, another
"experimental" test was done that came up positive. Mr. Johanns
would not describe it, but an Agriculture Department Web site said it
was an enhanced version of the "gold standard" test. Ed Loyd, an
Agriculture Department spokesman, said yesterday's announcement that
all positive rapid tests would now be confirmed both with the
immunohistochemistry test and a western blot "took care" of such
complaints and showed that the department was not complacent.
Mr. Johanns also ordered the Agriculture Department's national
laboratory in Ames, Iowa, to reassess the antibodies in its
immunohistochemistry test, because the British laboratory's
antibodies attached to the misfolded brain proteins, called prions,
that cause the disease, while the American laboratory's apparently
did not. The test is not purchased off the shelf, he said, and every
laboratory must make its own. Mr. Johanns said that the animal did
not have many prions and that they were concentrated in unusual areas
of the brain, so one laboratory's test might miss the infection while
another caught it.
[Byline: Donald G. McNeil, Jr.]
[The non-contributory remarks and comments have been deleted. Last
week I asked a senior colleague in Austin, Texas whether he could
confirm that this was a Texas cow, to which he replied, "No comment,"
so we can, I believe, safely assume that it was. Where it was raised
as a calf is another question awaiting answers. - Mod.MHJ]
Date: Tue 28 Jun 2005 1:17 PM
Source: OIE website [edited]
Bovine spongiform encephalopathy in the United States of America
(Date of previous case of bovine spongiform encephalopathy in the
United States of America reported to the OIE: December 2003 [in an
Information received on 27 Jun 2005 from Dr Peter Fernandez,
Associate Administrator, Animal and Plant Health Inspection Service
(APHIS), United States Department of Agriculture (USDA), Washington,
Report date: 27 Jun 2005.
A non-ambulatory or "downer" cow tested "inconclusive" for bovine
spongiform encephalopathy (BSE) when tested by a rapid screening test
in November 2004 but was confirmed positive in June 2005 using
western blot test and an immunohistochemical test carried out at the
OIE Reference Laboratory for BSE in Weybridge, United Kingdom.
As a downer, the cow was prohibited from entering the human food
supply. The carcass of the animal was incinerated.
Source of outbreak or origin of infection: unknown or inconclusive.
The affected cow was born before the United States instituted a
ruminant-to-ruminant feed ban in August 1997. The USDA has initiated
an investigation to determine the animal's herd of origin.
Date: Mon 27 Jun 2005 4:46 PM
From: Mary Marshal firstname.lastname@example.org
Source: Cattlenetwork, 24 Jun 2005 [edited]
Cattle Update: Canada Exceeds BSE Testing Target for 2005
Canada has surpassed its testing target established for 2005 for
bovine spongiform encephalopathy (BSE) surveillance. The target for
this year was 30 000 cattle and, as of 17 Jun 2005, there have been
32 363 samples collected and tested through the provincial and
federal laboratory network in Canada.
The level and design of BSE testing in Canada is in full accordance
with the guidelines recommended by the World Organisation for Animal
Health (OIE). The samples collected target the highest-risk cattle
within the national herd. This includes all animals over 30 months of
age that are dead, down, dying or diseased, and clinical suspects of
any age. This targeted surveillance program is crucial to defining
the level of BSE in Canada and to confirming the effectiveness of the
suite of measures in place to protect human and animal health from
the disease. Based on the intensity and sensitivity of the testing
program and the information collected in Canada's BSE investigations,
the evidence continues to demonstrate that the prevalence of BSE in
Canada is extremely low and continuing to decline.
"Surpassing this surveillance target at the mid-year point
illustrates the effectiveness of the national BSE surveillance
program and the high level of commitment from Canadian producers to
finding the disease," said Minister of Agriculture and Agri-Food Andy
In 2004, a BSE Surveillance Reimbursement Program was implemented
that provides payments to producers for their services when eligible
samples are submitted to the national program. These payments assist
producers in covering a portion of the veterinary examination fees
and carcass disposal costs. Many provinces have also demonstrated
their commitment by providing additional support to the reimbursement
program through increased laboratory capacity, education and
awareness campaigns, sampling assistance and financial supplements to
the federal payments. This collective effort is critical to a
successful national surveillance program and to the continued
demonstration of vigilance in animal and public health and food
safety in Canada.
[No comment. - Mod.MHJ]