OTTAWA -

Canada's food-safety watchdog wants the names of staff who have recently been out of the country and may have been exposed to swine flu.

The Canadian Food Inspection Agency contacted its managers Monday asking for a list of employees who have travelled since March 30.

"Management has asked JP to provide a list of which employees have travelled in the last 30 days (since March 30, 2009) and plan to travel in the next 30 days (up to June 8, 2009)," says an email obtained by The Canadian Press.

"JP" is Jean-Pierre St-Amand, the agency's head of facilities and security.

The precaution is being taken to prevent CFIA inspectors who may have come in contact with the H1N1 influenza virus from spreading the flu to pigs.

Some 220 pigs an Alberta farm recently caught the same swine flu strain that has sickened hundreds of humans worldwide.

Federal officials said over the weekend that a farmhand who travelled to Mexico and fell ill upon his return apparently infected the pigs with the H1N1 influenza virus.

It is the first time this particular swine flu virus has been found in pigs.

The country's top veterinarian, Dr. Brian Evans of the CFIA, has said it's common to see influenza in pigs and human transmission to pigs is known to occur.

Signs of swine influenza in pigs include fever, loss of appetite, weight loss, coughing and sneezing.

The virus generally does not lead to death in pigs, and affected animals usually recover within five to seven days.

All of the sick pigs on the Alberta farm are recovering or have recovered and the farm worker has also recovered.

The barn remains under quarantine. So far no other area hog barn has been affected.

Bob Kingston, head of the agriculture union representing federal food inspectors, commended the precaution.

"We don't have a problem asking employees if they've been travelling into areas where they may have contracted diseases," he said.

Kingston said it's his understanding that the agency is only asking about work-related travel, and not personal travel by inspectors to countries the virus has spread to.

The CFIA was not immediately available to comment.

The swine H1N1 virus, a never-before-seen combination of swine, avian and human genes, is believed to have jumped to humans a while ago and has been passing person to person.

The World Health Organization insists there's no evidence that pigs are passing the virus to humans, or that eating pork products poses an infection risk.

Last week, the WHO dropped the term "swine flu" -- a nickname that angered pork producers and led to a drop in pork sales -- in favour of its scientific name: "H1N1 influenza A."