OTTAWA, ONTARIO — Although the H1N1 flu virus has been found in a swine herd in Alberta by the Canadian Food Inspection Agency, the food supply is not affected and Canadian pork continues to be safe to eat, C.F.I.A. said.

It is believed that the pigs were exposed to the virus from a Canadian carpenter who had recently returned from Mexico and had been exhibiting flu-like symptoms, according to C.F.I.A. Signs of illness were subsequently observed in the pigs. The individual has recovered and all of the pigs are recovering or have already recovered.

The C.F.I.A. is taking a precautionary approach while further testing is needed to more fully characterize the virus. The herd has been placed under quarantine, and the agency is working with public health colleagues to determine the most appropriate next steps to ensure that public and animal health remain protected. The chance these pigs could transfer the virus to a person is remote, the agency said.

Influenza viruses do not affect the safety of pork, previously added the World Health Organization, Food and Agriculture Organization of the United Nations and other scientific bodies.

Canadian pigs are tested for influenza viruses on an ongoing basis across the country during routine investigations into respiratory illnesses. The C.F.I.A. has been working with provinces, territories, the swine industry and private sector veterinarians to enhance monitoring of swine herds for signs of illness and to maintain enhanced biosecurity measures on farms across the country.

This news has not changed doing business with the U.S. "First and foremost, this detection does not change the situation here in the United States," iterated Agriculture Secretary Tom Vilsack.

No sick swine have left the Alberta farm and the animals and premises have been quarantined, Mr. Vilsack added. "We are working closely with our C.F.I.A. counterparts to be kept abreast of the situation, and will await the final confirmatory test results, which could take anywhere from five days to two weeks," he said. "Canada has handled this situation appropriately and taken the necessary steps and precautions.

"(This) discovery will not impact our borders or trading with Canada," Mr. Vilsack continued. "As prescribed by the World Organization for Animal Health guidelines, any trade restrictions must be based on science so at this time, we are awaiting confirmatory test results before considering any action."

The Associated Press recently wrote that China has now expanded its ban on imported pork and pork products to include those from Alberta. A notice on China’s web site states pigs or pork products sent to China from Alberta after the declaration would be destroyed. Shipments already in the country will be released only after being certified as safe. China's government has already banned imports of pork and pork products from Mexico and a handful of U.S. states.