Canadian farmers take precautions as bird flu outbreaks hit U.S. dairy cattle

Beef cattle farmer Raquel Kolof of Gibsons, B.C., says she's extremely concerned about recent outbreaks of a dangerous form of bird flu — also known as highly pathogenic avian influenza (HPAI) — in dairy farms across at least eight U.S. states.

Though she says protections are in place to prevent similar outbreaks from taking place north of the U.S. border, and there have been no confirmed cases of bird flu in Canadian cattle to date, she says she's still worried "that it's coming up here."

"Cattle do move around … and 85 per cent of our beef market is handled in south Alberta, through massive, massive factories," said Kolof, the owner and founder of Hough Heritage Farms. "They all conglomerate, they spread to each other and then it spreads from there."

Despite that unease, experts say there's no cause for alarm right now thanks to national food safety standards and steps being taken by the Canadian Food Inspection Agency (CFIA) to ensure that food producers adhere to necessary biosecurity measures.

HPAI is a strain of influenza that causes "severe disease and high mortality in infected poultry," according to the U.S. Centres for Disease Control and Prevention (CDC).

HPAI typically spreads between birds and has a high mortality rate for avian species, according to Genevieve Toupin, the national veterinary program manager with the CFIA, whose team is responsible for the agency's ruminant and swine programs. 

She says the virus currently infecting U.S. cattle is the same that's been circulated by migratory birds flying along the Pacific-Central Flyway for approximately the past two years.

Thirty-two herds across eight U.S. states so far have been affected by HPAI infections since government agencies made the announcement almost four weeks ago. It's still not clear how the virus is spreading to and between dairy cattle.

While the virus's name implies it only affects birds, other animals — including mammals — can catch H5N1. 

"In fact, we've detected H5N1 in polar bears, sea lions, penguins, foxes, and the presumption there is they're getting it from eating dead birds," said University of Ottawa global health epidemiologist Raywat Deonandan, speaking with Dr. Brian Goldman, host of The Dose.

Symptoms among infected cattle include a sudden decrease in milk production, thicker milk, decreases in appetite and dry manure or constipation, according to the CFIA.

Humans are susceptible to HPAI, though cases are rare and there has been no confirmed human-to-human transmission. 

Since 2003, nearly 900 people worldwide have been infected with H5N1, according to the World Health Organization. Canada has seen only one confirmed case, in 2013.

Infection occurs if the virus gets into a person's eyes, nose or mouth, or is inhaled, according to the CDC. Symptoms in humans resemble influenza, including cough, shortness of breath, fever and body aches.