OTTAWA - Canadian health officials on Tuesday announced the first case of turkeys catching the H1N1 flu in this country, likely from humans, and urged farm workers to get vaccinated soon.

The outbreak on a farm in Ontario province is the second case in the world, after Chile reported a case in August.

Officials said the flock in Ontario province had been quarantined and none of the birds or their eggs had entered the food chain. But they warned of a minimal risk to human health as the virus mutates going from humans to animals.

"This essentially human virus has been identified previously in swine and in poultry. Our working hypothesis is that this situation likely involved human-to-bird transmission," said Ontario chief veterinarian Deb Stark.

"Although rare, this finding is not unexpected," she told a press conference.

"The risk to human health from this situation is minimal," said Arlene King, Ontario's chief medical health officer.

"But it is the clarion call to people who work with livestock to get both the seasonal and the H1N1 flu shot."

"The risk is the potential changes to the virus against which people could have reduced or no immunity," King said.