The strain was discovered during a routine inspection of farms within a three-mile radius of the farm where the original outbreak was reported.

Although the new discovery will lead to the culling of birds at the farm to prevent the spread of the virus, this is a precautionary measure, and health risks remain minimal.

There are many low-pathogenic strains of avian influenza that lie dormant in large sectors of the bird population but do not cause infection in humans. It is believed that the H5 strain found in Canada is a low-pathogenic variety and not the H5N1 strain that has caused more than 65 deaths in Asia.

The United States, Hong Kong and Taiwan have placed temporary bans on the import of poultry from British Columbia; Japan has extended its temporary ban to cover all of Canada.

Meanwhile:

-- China has reported a new fatality from bird flu. A 35-year-old woman died Tuesday of avian influenza. She was a farmer and is believed to have contracted the disease in the course of her work.

There have been three confirmed reports of avian flu in humans in China and two deaths. A poultry worker from Anhui was confirmed to have died of the disease Nov. 10.

A 9-year-old boy was confirmed to have been infected with avian influenza but survived. His sister is widely believed to have died from bird flu, but the infection was never confirmed.

-- Russia has reported the deaths of 250 swans in the Volga River delta. It is believed the swans were infected with an H5 strain of avian influenza, but the results are yet to be confirmed.

-- Vietnamese scientists studying avian influenza have released some positive news for which we may all be thankful: It appears that slight changes have occurred in the virus at the genetic level, and it has become less virulent as a result.

Vietnam's National Institute for Hygiene and Epidemiology has been studying the virus for more than two years. Samples of avian influenza taken by the institute early in 2004 showed a virulence percentage of 99.1 percent.

Recent samples, however, show a virulence of 98.2 percent.

While this is a small percentage decrease, it has the potential for significant changes in the spread of bird flu.

Nguyen Thuy Hoa, head of the institute's Epidemiology Department, explained that the genetic alterations may have occurred as the strain adapted itself to humans. The decreased virulence has led to a higher rate of avian-influenza infection in humans, but those affected suffer milder symptoms and are exposed to a lower risk of death from the disease.

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