By Ian Karleff
TORONTO (Reuters)
- Canadian scientists are testing a vaccine in cattle this month
that could eradicate a deadly strain of the E.Coli bacteria at
the source, and prevent costly ground beef recalls.
The National
Research Council has teamed up with Foragen Technology
Ventures
Inc., a seed capital fund of the Royal Bank of Canada (Toronto:RY.TO
- news), to test an oral vaccine in cattle at the Veterinary Disease
Organization in Saskatoon.
Foragen said
it will invest up to C$2 million to determine whether the vaccine,
which has demonstrated in mice the ability to kill the 0157 E.Coli
strain, is commercially viable.
``We are
trying to get quantitative results and then look at probably forming
a company around the technologies,'' said Dr. Murray McLaughlin,
President of Foragen and Saskatchewan's former Deputy Minister
of Agriculture.
Cattle are
the primary source of the 0157:H7 variety of E.Coli, a potentially
deadly pathogen that can cause life threatening infections, such
as the recent outbreak in the rural town of Walkerton in May that
contributed to six deaths.
The 0157
strain of E.Coli, known as the ``hamburger disease'' has shown
up in a number of ground beef shipments lately, and on Wednesday,
forced Winnipeg's Lakeside Packers to recall a 65,857 kg shipment
exported to the U.S.
Earlier this
month, a second Milwaukee Sizzler steakhouse was closed after
a three year old girl died and about 50 people were infected with
food borne 0157 E.Coli.
A recent
report by the U.S. Department of Agriculture estimated that 89
percent of U.S. beef ground into patties contains traces of the
deadly E.Coli strain.
And the Centre
For Disease Control in Atlanta estimates that about 52 Americans
die annually from food tainted with the bacteria and 73,000 are
infected.
Dr. Malcolm
Perry, director at the National Research Council's Bacterial Pathogenesis
Group, said results from the vaccine trials in cattle should be
known fairly soon, and then it must be shown to be safe and cheap.
``If this
works, it should be fairly easy to produce herds that are free
of E.Coli. Although we can never say it will never reoccur, I
think it has a good chance of working, and there is nothing else
on the horizon,'' said Perry.
Perry said
research into the deadly 0157 molecule on the surface of the E.Coli
bacteria -- a bacteria that is present in humans and animals and
actually maintains health -- started 20 years ago when outbreaks
first hit North America.
His team
was the first to map a molecular model of 0157, and to create
an antibody that attached itself to the molecule, which in turn
was used as a specific diagnostic agent.
This process
led to the discovery of other unrelated bacteria that also carried
the 0157 molecule, but were not toxic.
It is these
unrelated bacteria that have been formulated into a vaccine and
orally administered to small animals by Perry's team.
Perry said
that not only did the vaccine demonstrate the ability to protect
the animals from contracting E.Coli, but also de-colonized the
animal of existing E.Coli.
``The question
is whether you can transfer this from small animals to cattle,
and that's the experiment we got the external funding from Foragen
to do,'' said Perry.
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