Published Date: 2005-06-14 23:50:00
Subject: PRO/AH> BSE, bovine - USA (05): susp.
Archive Number: 20050614.1664
BSE, BOVINE - USA (05): SUSPECTED
A ProMED-maili post
ProMED-mail, a program of the
International Societyfor Infectious Diseases
Date: 14 Jun 2005
From: ProMED-mail <email@example.com>
Source: Bloomberg.com, 13 Jun 2005 [edited]
USDA Says Suspect Mad-Cow Animal Was Born Before 1997 Feed Ban
The animal involved in the latest possible U.S. mad cow case was born
before August 1997, when the government imposed new feed rules designed to
prevent the spread of the brain-wasting livestock illness, the United
States Department of Agriculture (USDA) said.
USDA spokesman Ed Loyd, while not providing the birth date or other
details, said the animal was born before the U.S. and Canada banned the use
of ground-up parts of cattle in livestock feed as a protein source.
Scientists say cattle contract mad cow disease, clinically known as bovine
spongiform encephalopathy, or BSE, by eating infected parts of other animals.
That means that if tests confirm that the animal was infected, it may have
contracted the disease prior to the 1997 ban, and that the feed
restrictions have been working as designed, said Dan Vaught, a livestock
analyst with A.G. Edwards & Sons Inc. in St. Louis.
"The chances of having an animal born after the 1997 ban be infected
becomes extremely small, since the eating of infected materials is the only
known way in which BSE is transmitted," Vaught said.
The Agriculture Department announced 10 Jun 2005 that a tissue sample that
had tested positive in a rapid screening test in November 2004, then
negative in more reliable immunohistochemistry testing, had again tested
positive when a different rapid screening procedure was performed.
The sample will be sent to the U.K.'s veterinary laboratory in Weybridge,
England, where it will again be subjected to the IHC test. Results will
probably be available next week, Loyd said. Mad cow disease, which has a
fatal human variant, first surfaced in the U.K. in the 1980s and the
country had had extensive experience with the disease.
The Agriculture Department's inspector general had ordered the sample
retested, along with 2 other samples that had tested positive in
screenings, as part of a review of the USDA's mad cow disease surveillance
program. All 3 samples had negative results in IHC testing.
These 3 cases had provided the only "inconclusive" results out of 375 360
samples screened as part of an expanded mad cow disease surveillance
program that began in June 2004, the USDA said.
The department designed the surveillance program to determine the
prevalence of mad cow disease in U.S. herds after an infected cow was found
in Washington state in December 2003, the only confirmed case in U.S.
history. That animal was later traced to Canada, which has had 3 other BSE
[Unfortunately the feed ban has not been uniformly enforced, so it will not
be unexpected when the US has an animal affected with BSE born after the
[feed] ban (BAB) was to have taken effect. Although feed manufacturers are
complying with the rules, on-farm feed mixing appears to be under the
radar screen of the Food and Drug Administration's (FDA) enforcement of
the feeding ban.
Although the feed ban rule was put into place by the FDA, it is the USDA
that is charged with animal diseases and animal health. So when the feed
ban is violated on a farm (for example, by on-farm feed mixing), FDA does
not appear to have an enforcement arm; but as the disease has a long
incubation, it is outside of the jurisdiction of the USDA. Again, it will
not be surprising if the US has a BSE-affected animal that is born after
the ban. - Mod.TG]