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Published Date: 2003-05-25 23:50:00
Subject: PRO/AH> BSE, bovine - Canada (Alberta) (05)
Archive Number: 20030525.1287

BSE, BOVINE - CANADA (ALBERTA) (05)
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International Society for Infectious Diseases
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Date: 25 May 2003
From: ProMED-mail <promed@promedmail.org>
Source: Toronto Star, 24 May 2003 [edited]
http://www.thestar.com/NASApp/cs/ContentServer?pagename=thestar/Layout/Article_Type1&c=Article&cid=1052251641936&call_pageid=968332188774&col=968350116467

13 farms in 3 provinces have now been quarantined as investigators focus on
the possible use of contaminated feed as the source of Canada's mad cow
disease outbreak.

4 more farms -- including 3 in British Columbia -- were added yesterday to
the list of those isolated in Alberta and Saskatchewan in the effort to
find out how a cow became infected with bovine spongiform encephalopathy
(BSE).

Alberta Agriculture Minister Shirley McClellan said she's "very, very"
concerned that the animal from a farm near Wanham, in northwestern Alberta,
may have been stricken with BSE, by eating feed containing the protein of
cows or sheep. The use of cow or sheep protein in cattle feed was banned
in 1997.

McClellan said even though the Canadian Food Inspection Agency (CFIA) has
found a high degree of compliance with the rules, "in the end we depend on
the integrity of the producers to comply with the feed bans" and that may
not have happened.

"I don't think it (the use of banned feeds) is widespread. I don't believe
that," she said at a news conference. "I think the majority of the
producers understand the seriousness and the importance of those rules."

The feed ban, which was part of the fallout from the mad cow crisis that
devastated the British beef industry in the 1990s, is designed to protect
cattle from the disease. Scientists suspect the disease is spread by the
use of the animal proteins in food given to cattle. BSE attacks brain
tissue, leaving it spongy and full of holes.

Dr. Brian Evans, chief veterinary officer with the CFIA, said 4
possibilities remain for contamination of the cow, which was declared unfit
for human consumption when it was slaughtered 31 Jan 2003. It wasn't tested
for BSE until last week.

Given the incubation period of up to 8 years for BSE and the fact that the
stricken cow was estimated to be between 6 and 8 years old, it may have
become sick by feed before the ban, Evans said. It may have also been given
illegal food after the ban. [Or perhaps the feed on hand was being fed,
even as the feeding ban took effect. - Mod.TG]

Evans also said the cow may have been imported from another country where
it was exposed to BSE, or it may have been stricken spontaneously -- a
likelihood, he said, of about 1 in 10 million.

But even though the investigation has expanded to include13 farms -- 8 in
Alberta, 3 in B.C., and 2 in Saskatchewan -- Evans insisted that's a
positive development and that there is still evidence of just 1 cow being
infected with BSE.

"This clearly indicates to us the progress that we are making and reflects
the fact that the investigation is advancing but not the disease," he said
at an Ottawa news conference. "The increasing number of herds under
quarantine is a normal occurrence in an investigation of this type and does
not indicate that the situation is getting worse."

The 3 small-scale mixed livestock farms in B.C. -- 2 near Vancouver and the
other near Prince George -- are suspected of having bought poultry feed,
which was made from the rendered carcass of the infected cow.

Alberta farms in Wanham, Evansburg, Barrhead, Tulliby Lake, and Vermilion
have been quarantined, as have Saskatchewan farms in Lloydminster and
Baldwinton.

Evans said the probe has determined that the suspect feed was not given to
cattle.

"And to the extent that we have been able to complete the investigation, we
have verified that since the feed arrived on those farms, no animals have
moved off those farms into the food system," he said.

From the infected herd in Wanham more than 200 cows and calves are being
slaughtered and tested for BSE, with results expected by early next week.

Evans said that officials hope to be able to soon lift quarantines on some
of the farms if there's evidence to show the sick animal wasn't there and
there are no other risks.

Federal and provincial agriculture ministers discussed the issue in a
conference call yesterday, and Canadian Press reports one minister
suggested a widespread slaughter of all quarantined cattle may be needed to
restore public confidence in Canadian beef.

"It's my view that we might want to do that," said Saskatchewan Agriculture
Minister Clay Serby. "That's about erring on the side of safety." Serby
said the food inspection agency will likely decide on that next week.

McClellan and Alberta's chief veterinarian, Dr. Gerald Ollis, were on the
hot seat again yesterday as they defended the fact that it took nearly 4
months to test the infected cow for BSE. Both insisted that it was given a
low priority because it was not destined for human consumption and not
clearly suffering mad cow.

"It was condemned for pneumonia," Ollis said. "Pneumonia can weaken an
animal and it may not be able to get up, and there were obvious lesions of
pneumonia."

--
ProMED-mail
<promed@promedmail.org>

[The minister hints of mass slaughter to regain public confidence. This is a
costly move, as there will likely be an outcry that the government should
provide some support if they are willing to condemn the animals. It may not
gain public confidence, thereby making it a costly strategy without the
desired outcome. BSE cannot be passed by casual contact from one animal to
another. It requires contaminated feed, or contamination during gestation.
Therefore logic and science would indicate tracing the animal's offspring
and tracing the feed given to the animal and its offspring -- which is being
done. - Mod.TG/JW]

See Also