Canada bird flu believed low pathogen strain

WINNIPEG, Manitoba, June 21 (Reuters) The Canadian Food Inspection Agency has said that all samples taken from a backyard flock of geese in Eastern Canada have tested negative for any strain for bird flu.

''So far we have nothing but negative results from all samples that have been taken from Prince Edward Island,'' said CFIA veterinarian Dr. Jim Clark yesterday.

All indications show that a dead gosling from the flock carried a low-pathogen strain of bird flu that is not a threat to human health.

Canada said last Friday that the gosling had tested positive for H5 avian flu at a test at a lab in Atlantic Canada. The noncommercial flock of 35 to 40 chickens, geese and ducks was euthanized and a neighboring backyard flock was quarantined.

Samples were then sent to a more sophisticated lab in Winnipeg, Manitoba, and tested negative.

Clark said one reason the Winnipeg laboratory did not detect any virus was that the material may have degraded during the move from Atlantic Canada.

''There had to be an AI (avian influenza) to be detected in the Atlantic. That's a given. That's a scientific fact,'' he said.

''I don't believe that what we're dealing with here is the H5N1 Asian strain for a variety of reasons, simply because if that virus was present it would have killed the majority of birds on the premises and it would have been reasonably detectable over the long term,'' Clark said.

The highly pathogenic H5N1 strain of the virus has not yet been found in North or South America although it has been found in parts of Asia, Europe and Africa.

Not all H5 viruses are highly pathogenic and not all will cause severe disease in poultry. Canada has had low pathogenic outbreaks in the past.

The last outbreak was in November 2005 in Canada's western province of British Columbia, when the low-pathogenic H5N2 strain was discovered. The birds did not show signs of illness but 60,000 ducks and geese were culled.

There was a highly pathogenic case of H5N9 bird flu in 1966 and a case of high pathogenic H7N3 in 2004.

Prince Edward Island has only seven commercial chicken farms and there are none within a 10 km radius of the affected farm, according to industry group Chicken Farmers of Canada.

REUTERS PDS BST0505