It may take a week to two weeks to get the final test results, but early indications that the H1N1 influenza A virus has infected an Alberta swine herd, has shaken that country’s pork industry and raised concerns about the potential for new hybrid viruses to emerge.
According to Canadian authorities preliminary test results May 2 detected the virus in an Alberta herd and that it probably came from a Canadian carpenter who works on the farm and fell ill with the flu when he returned from a visit to Mexico in mid-April.
The worker had contact with the pigs on April 14 and about 220 pigs in the herd of 2,200 began showing signs of sickness on April 24, according to Brian Evans of the Canadian Food Inspection Agency (CFIA).
Both the carpenter and the pigs have recovered, the CFIA said. The farm remains quarantined.
Animal health officials say the Canadian case is not a surprise.
“The human-to-animal transmission that occurred in Canada does not come as a surprise as influenza viruses are capable of transmitting from humans to animals,” reports Joseph Domenech, chief veterinary officer of the United Nations Food and Agriculture Organization.
Peter Ben Embarek of the World Health Organization said it appears that the virus isolated from the Canadian swine is no different from the flu virus spreading among humans. “There is no sign that it has changed at all. But this could of course happen like with any other flu viruses,” he says. He added it’s important to increase surveillance in humans and animals to detect any possible mutations.
Biosecurity Precautions
Take these on-farm surveillance steps from the National Pork Board to prevent this new flu virus from entering herds and to protect the health and safety of both people and pigs:
--Establish, implement and enforce strict sick leave policies for workers exhibiting flu-like symptoms. Ill workers should not be allowed to enter swine facilities for at least seven days after presenting signs of respiratory illness.
--Implement biosecurity for workers reporting international travel. Consider banning the entry of workers who have traveled internationally, especially to Mexico, into your operation. If necessary, require these people to wear face masks, or preferably N95 respirators, and gloves.
--Limit visitors to swine facilities. Exclude all but essential service personnel into your hog barns.
--Follow other generally accepted biosecurity practices. Pay attention to ventilation, ensuring that systems minimize air recirculation to reduce the exposure of pigs to viruses from other pigs and to reduce their exposure to human influenza viruses. Enforce basic hygiene practices. Require workers to shower and change into farm-specific clothing and boots before entering swine facilities. Implement and enforce the use of personal protective equipment. Vaccinate pigs against the influenza virus. Recommend that all workers be vaccinated against the seasonal influenza virus.
Should respiratory illness be observed in pigs, contact your swine veterinarian immediately, especially if the onset of illness appears unusual. If workers collect samples to be sent to the diagnostic lab, require use of personal protective equipment including a respiratory mask and safety goggles.
Talk to your veterinarian if flu-like symptoms occur in any of the workers who have had contact with the pigs and report that observation when submitting samples to the diagnostic lab.