The A/H1N1 virus is spreading faster than anticipated, Chinese experts said yesterday after about 200 pigs were found infected with the virus in Canada on Saturday.

"The virus could be stronger than we expected," said Yang Hanchun, a professor at China Agricultural University.

"The case tells us we need to enhance vigilance at pig farms, too," he said.

The Canadian Food Inspection Agency said a traveler carried the virus from Mexico to Canada, infecting his family and a herd of swine.

The herd in the western province of Alberta apparently caught the virus from a carpenter who traveled recently to Mexico, the epicenter of a swine flu outbreak that has spread to 18 countries and regions.

It was the first time that a human-to-pig transmission has been reported.

The case has intensified fears, prompting global organizations to reassure people that pork products are safe.

"In light of the spread of H1N1, and the rising concerns about the possibility of the virus being found in pigs and the safety of pork and pork products, we stress that pork and pork products, handled in accordance with good hygienic practices will not be a source of infection," four organizations said in a statement yesterday.

They are the World Health Organization, the Food and Agriculture Organization of the United Nations, the World Organization for Animal Health and the World Trade Organization.

Yang said human-to-animal transmission of flu viruses was not new, so people should not be panic. He also said there is no evidence to suggest that the H1N1 virus can be passed through pork products.

China announced an import ban on pork and pork products from Alberta yesterday.

Pork imports from some US states and Mexico were banned last week.

(China Daily?May 4, 2009)