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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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