May 14, 2004 (CIDRAP News) – Canadian authorities say further tests have shown that geese on a farm in southern British Columbia were not infected with a dangerous avian influenza virus, but test results on ducks from the same farm are still awaited.
Initial tests of geese and ducks on the farm had indicated possible antibodies to an H5 virus, raising concern about the possibility of H5N1, the subtype blamed for the recent widespread avian flu outbreaks in East Asia. The farm is at Abbotsford in the Fraser Valley, where authorities have been destroying millions of poultry because of an outbreak of H7N3 avian flu.
In a statement released late yesterday, the Canadian Food Inspection Agency (CFIA) said, "Further testing has revealed that geese on a Fraser Valley farm were not infected with either H5 or H7 avian influenza. There is strong evidence indicating the geese were exposed to the H6 avian influenza virus. The H6 virus is not associated with serious animal or human illness."
Further testing is expected to clarify the status of ducks on the farm, the CFIA said. In an Associated Press (AP) report today, Dr. Cornelius Kiley of the CFIA estimated the tests on the duck samples would take another week. The agency said no illness has been seen in the flock.
The Abbotsford farm is within 3 kilometers of farms hit by the H7N3 outbreak, and the flock there was scheduled to be sacrificed in the effort to stop the outbreak, the CFIA said.
The agency said it is not surprising to find various avian flu virus subtypes in birds raised outdoors, where they have contact with wild birds. The latter are known to carry various virus strains, most of which don't cause serious illness in birds.
Meanwhile, the AP reported today that more than 21 days have passed since the last avian flu outbreak in Thailand, raising hopes that the country may be free of the disease. The report quoted Agriculture Minister Somsak Thepsuthin as saying, "We admit that we're not sure bird flu is totally cleared out of Thailand. But we haven't found the disease anymore in farms."
Somsak said a farm in the northern province of Uttaradit was the site of the last reported outbreak, and no signs of the disease had been seen there since Apr 19, according to the story.
More than 37 million birds have been destroyed in the battle to contain avian flu in Thailand. The country has had eight fatal human cases of H5N1 infection. New outbreaks have forced Thai officials several times to postpone plans to declare the nation free of the disease.