Robert Roos  News Editor

Jan 26, 2009 (CIDRAP News) – Canadian authorities have confirmed that an H5 avian influenza virus, probably low-pathogenic, has surfaced on a turkey farm in southern British Columbia.

Canadian news agencies said authorities were preparing to cull up to 60,000 turkeys on the farm near Abbotsford, southeast of Vancouver in the Fraser Valley.

In a Jan 24 news release, the Canadian Food Inspection Agency (CFIA) confirmed that an H5 virus was found on the farm and said initial tests indicated that it is low-pathogenic. Further tests were under way to determine the precise subtype and strain, the agency said.

A private veterinarian submitted turkeys from the farm to British Columbia"e;s Animal Health Centre for testing because of a "respiratory problem with no significant mortality," according to a report that Canada filed with the World Organization for Animal Health (OIE) on Jan 24.

Canada"e;s National Centre for Foreign Animal Diseases in Winnipeg, Man., confirmed that the virus was an H5, the OIE report said. It said gene sequencing showed that the virus was 99% similar to an H5N2 virus recovered from a green-winged teal in California in 2007.

The CFIA said all birds on the farm would be euthanized and disposed of and that the agency would oversee cleaning and disinfection of the barns, vehicles, equipment, and tools.

A CBC News report said the CFIA planned to kill the birds by sealing the barns and flooding them with carbon dioxide. Workers will then mix the carcasses with organic material in the barn to raise the temperature as high as 50°C during decomposition and thereby kill the virus, the story said.

The OIE report said the affected barn contained about 28,000 turkeys. But the CBC report and other news stories cited plans to cull up to 60,000 birds.

The CFIA said it was restricting the movement of poultry and poultry products within 3 kilometers of the outbreak site. The restrictions affect 23 other farms, according to the CBC report.

The Fraser River Valley had a large outbreak of highly pathogenic H7N3 avian flu in March 2004, which affected as many as 40 commercial farms and led to the culling of 17 million birds. In addition, a low-pathogenic H5 virus was found on a poultry farm in the area in November 2005.

In other developments, two new outbreaks of the deadly H5N1 virus have been reported in backyard poultry flocks in Egypt, according to online information from the Egypt-based project Strengthening Avian Influenza Detection and Response (SAIDR).

Both outbreaks occurred in Alexandria governorate, SAIDR reported. An outbreak in Khorshid district involved 100 chickens and 10 ducks, and one in El Mamoura district affected 10 chickens and 5 ducks.