May 14, 2004

Canada Alert For New Bird-Flu Strain

It will take at least a week for infectious-disease experts to confirm the accuracy of tests that indicate a dangerous new strain of avian influenza has emerged in the Fraser Valley of British Columbia, according to a report in Thursday's Globe and Mail newspaper.
 
But health and agriculture officials, who closed a school on Tuesday and destroyed more than 37,000 ducks and geese on a nearby farm, are not taking any chances. If the H5N1 virus is loose in British Columbia, it would raise serious public-health concerns.
 
Perry Kendall, the chief provincial health officer, in the article said routine checks by the Canadian Food Inspection Agency (CFIA) detected a new strain of avian flu at a duck and goose farm Monday.
 
"The little wrinkle is that the virus they have found might be an H5 and not the H7 that we have been dealing with to date," Dr. Kendall said.
 
"We don't really know [the health implications]. People are sensitive to H5 because the H5N1 strain in Thailand and Vietnam did prove capable of crossing the species barrier and infecting humans, particularly children who were in close contact with chickens. It had a fairly high mortality in those kids."
 
Dr. Kendall said concern over the possible presence of a new virus led officials to close the King Traditional School, which has 367 pupils ranging from kindergarten to fifth grade. No one was sick at the school, but it is next door to the duck and goose farm.
 
Cornelius Kiley, the CFIA veterinarian in charge of the avian flu eradication plan in the Fraser Valley, said the school was closed "out of an abundance of caution."
 
He said tests showed that birds on the farm had avian flu antibodies, but were generally healthy. The results indicated the fowl on the Fraser Valley Duck and Goose Farm, which is the main supplier of Peking duck in Western Canada, had been exposed to avian flu, but had recovered.
 
Dr. Kiley said the initial tests indicated an H5 virus, but were not conclusive and did not suggest what N number it might be. Further tests are being conducted.
 
"If the testing goes according to plan, we should have confirmation, verification of the H number within the next few days. But it may take a week to 10 days before we can confirm the N number," he said in the article.
 
Nailing down the exact nature of the virus is important because the H5N1 strain, which has killed more than 20 people in Asia, can cross from birds to humans.
 
The World Health Organization has warned that H5N1 "may have a unique capacity to cause severe disease, with high mortality, in humans."
 
H5N1 has never been detected in North America, but has infected poultry in Korea, Vietnam, Japan, Thailand, Cambodia, China, Laos and Indonesia this year.
 
In an attempt to control an outbreak of the H7 strain that began in February, the CFIA has killed about 19 million birds in the Fraser Valley over the past several weeks. H7 can be fatal to chickens but poses no health risk to humans.
 
Ken Falk, owner of the Fraser Valley Duck and Goose Farm, in the article said the government has overreacted to a blood sample that may be inaccurate. He noted that ducks and geese can develop immunity to avian flu and he had asked the CFIA to exempt his flock from culling.
 
"We've been working with these people for the past six weeks trying to work out a solution. Then, based on a flimsy suspicion, a flimsy excuse, they call in the gas crews."
 
Falk accused the CFIA of doing a sloppy job on the avian flu problem and argued that officials should have waited for confirmed test results before taking action.
 
"Their inspectors came and went and kind of wandered all about the countryside and this thing spread out of control. They bungled it from the world go," he said.