Canadian farm culls 500 swine flu-infected pigs

Monday, May 11, 2009

Canadian farm culls 500 swine flu-infected pigs

English: Illustration of antigenic shift (Photo credit: Wikipedia)

By CHARMAINE NORONHA,Associated Press Writer AP - Sunday, May 10

TORONTO - Canadian officials said Saturday that almost 500 hogs quarantined on an Alberta farm after they were diagnosed with swine flu have been culled because of overcrowding.

Dr. Gerald Hauer, Alberta's chief provincial veterinarian, said the quarantine left the farm unable to ship hogs to market, resulting in an overpopulation of pigs.

"They were not culled for being sick," Hauer told a news conference. "They were culled because of animal welfare concerns. Living conditions on the farm became unacceptable because of overcrowding. A farm of that size ships 100 out to market weekly so we had to get them out because several weeks of production remained on the farm."

The cull included healthy animals, pigs that had recovered from the virus, as well as hogs with flu symptoms, he said.

Hauer also stressed that the culled pigs and the virus will not enter the food chain since they have been disposed of through rendering, which treats the culled carcass with heat, killing the virus in the process.

Officials identified that the pigs had been infected with swine flu last weekend, apparently by a Canadian farm worker who recently visited Mexico and got sick after returning to Canada.

Dr. Brian Evans, executive vice president with the Canadian Food Inspection Agency, stressed that the pigs do not pose a food safety risk, adding that swine flu regularly causes outbreaks in pigs.

According to the U.S. Centers for Disease Control and Prevention, studies have shown that swine flu is common throughout pig populations worldwide, with 25 percent of animals showing antibody evidence of infection.

Evans said normally detecting influenza in pigs would not generate a response from food safety officials, but officials alerted the public after the international flu outbreak.

The news that the H1N1 virus had been found in pigs made international headlines on May 2. Though genetic analysis of the new virus shows it is the product of reassortment (gene swapping) between two swine flu viruses, the virus had not been found in pigs to that point.

Officials said the pigs were likely infected in the same manner as humans worldwide, and that the virus is acting no differently in the pigs than other swine flu viruses.

Evans noted that the there was a remote chance that the infected pigs could transfer a virus to a person and that the new virus has shown no signs of mutation when passing from human to pig.

Hauer said Saturday that the flu has not spread beyond the farm and that 1,700 pigs remain under quarantine.

From Yahoo! News; see the source article here.