'We can’t just wait for nature': How BC science and farmers are battling the bird flu epidemic

A farmworker knocked on James Krahn’s door in late October last year. The turkeys were sick. They didn’t know what it was for sure, but in the fall, one disease is more likely than the rest: avian influenza.

Krahn called BC’s sick bird line, which connects callers directly to the Canadian Food Inspection Agency’s rapid response team.

“It was hard to make that call,” Krahn said. “It’s something no farmer wants to do, but [we know] we’ve got to get ahead of it.”

Within a few hours, officials from the CFIA were at the farm, taking samples to analyze at the nearby Animal Health Centre laboratory in Abbotsford. By that evening, Krahn had the results. It was bird flu. His entire flock would have to be euthanized.

It was hard to hear—and the situation was made even more devastating by another one of his flocks falling victim to the virus a week later. It also wasn’t the first time Krahn and his brothers, who own multiple poultry barns in Abbotsford, had faced avian influenza.

A (relatively) brief history of avian influenza

Bird flu is not new. Originally called “fowl plague,” the disease was most common in Africa and Asia, although it has since spread to Europe, North America, Central America, South America, and Antarctica. In 1955, scientists were able to identify the virus itself, and less than two decades later began the letter-number naming system that helps identify flu viruses today.

(The two most-common avian influenza viruses in Canada, H5N1 and H7N3, are named using this system—as is swine flu, or H1N1. The H and N numbers refer to how many proteins of a certain type each virus has. There are different subtypes of each virus, which we talk about in more detail in our story on bird flu in cattle. The most common subtype of H5N1 in Canada is D1.1, which sent a teen to hospital last fall.)

Flu viruses, as a whole, are extremely contagious. Avian influenza is no exception.

The virus is predominantly found in wild birds—some of whom carry a low pathogenic version of the virus without getting sick. The virus spreads through feces and saliva, and may also move from host to host via feathers or dust.

When the virus finds its way into a poultry flock, the result is deadly. Within two weeks, the birds become quiet and melancholic, their wattles and combs become inflamed, and the skin under their eyes becomes swollen. Diarrhea and hemorrhaging are common, and respiratory distress is also likely. They produce fewer eggs, and those eggs have soft shells, or no shell at all.

And then, the birds die.

There is no treatment for the disease. It is also not a pleasant way to go: the birds typically die after multiple organs fail, with the associated consequences.

With the virus able to replicate itself so quickly—and potentially escape the confines of the barn—Canadian regulations require farmers to kill all their birds as soon as one is diagnosed with avian influenza. Once the birds are dead, the facility is disinfected according to a strict routine.

(The CFIA says the birds are “humanely destroyed using internationally recognized methods.” In 2014, infected birds were killed by sealing the barns and filling them with carbon dioxide, making the birds unconscious before suffocating them.)

Canada experienced its first commercial case of avian influenza in March 2004, at a chicken farm in BC. Although the chickens were killed, and the farm quarantined, the H7N3 virus spread to more than 50 flocks in the region. By June the outbreak was over, and H7N3 seemed to have gone away.

The next year, Canada had begun an annual survey for influenza in wild birds—an effort that continues to this day.

Another outbreak hit British Columbia in 2014, this time with an H5N2 virus. That outbreak resulted in 12 Fraser Valley farms needing to euthanize 240,000 birds. The province was declared disease-free after six months.

It wasn’t until 2022 that BC faced another large wave. There are often low pathogenic bird flu viruses biding their time in wild flocks—viruses that cause only mild illnesses, or none at all. But a new H5N1 virus came to the fore in 2020 that was highly pathogenic. It spread across continents, killing wild ducks, geese, and other waterfowl. It began spilling over into marine mammals. And the birds in western North America brought it to poultry farms.

In May 2022, the virus infected birds at an Abbotsford poultry farm. In the remaining seven months of that year, 70 commercial operations in the Fraser Valley were affected. And every fall since, avian influenza has infected birds at dozens of poultry operations.

Among the farms infected in 2022 and 2024 were poultry operations run by James Krahn and his brothers, Dale and John. The Krahn brothers own seven poultry barns in the area surrounding Abbotsford’s airport. Together, they have 180,000 laying hens, 100,000 chickens, several hundred turkeys, and a feed mill. And although their farms are larger than BC’s average, the brothers face the same emotional and financial toll as other producers.

“It’s something that you’re not necessarily always prepared for as a farmer,” James Krahn said about getting avian influenza in a flock.

“It’s always in the back of your mind. But … when you have something like this happen to your farm, it’s a huge challenge, and it’s definitely devastating.”

Battling an infection from the boots up

The challenge starts at the beginning, with farmers trying to stop avian influenza from getting into their barns.

Biosecurity efforts can be as basic as washing boots and as complex as government orders against bird movements. British Columbia’s biosecurity measures currently encompass both sides of the spectrum.

“Farm gates are literally closed,” said Shawn Hall, a spokesperson for the BC Poultry Association.

Poultry producers are placed on a red biosecurity level at the beginning of the avian influenza “season”—the highest level of warning. Visitors are not allowed on farms unless they are absolutely essential. Even feed trucks can only come with appointments, and only after they are thoroughly washed before driving through the gate. Employees have to wear personal protective equipment in the barns, and boot washing is a must.

At a provincial and federal level, the BC Ministry of Agriculture and the Canadian Food Inspection Agency work together to map infected premises, establish quarantine zones, and create systems for how producers need to respond to infections.

BC’s Chief Veterinarian Theresa Burns also has specific tasks of her own. She is the person responsible for creating health orders in the province, deciding exactly what industry needs to do to prevent infections from spreading between farms.

She said she uses a variety of data to help make those calls, including information on the level of wild bird infections in the province, and the contamination of wetland sediments. She also considers what is happening in neighbouring provinces and states—since the virus is transmitted by migrating birds—and monitors the weather conditions in various parts of BC.

Currently, there is an order preventing organic birds from going outside, because of what Burns calls “high environmental contamination” with the virus. There is also an order preventing “co-mingling” between birds, which stops people from attending poultry swaps and fairs with their birds.

“We’re trying to control what is controllable, to reduce the risk as much as possible,” Burns said.

To help producers understand the provincial requirements, BC’s poultry associations established an emergency operations centre to send information to producers about bird flu.

“They’re regularly communicating information out to farmers about the sick bird line, what the actions are that they need to take,” Hall said. The EOC operates daily during the avian flu season, and closes when cases disappear.

The seasonality of the outbreaks influences how all levels of government and industry manage the virus. At BC’s Animal Health Centre in Abbotsford, tests are analyzed seven days a week during the fall flu season—a system that has been in place for the last three years.

The lab technicians check samples from birds across British Columbia, and often return results to the farms the same day so they can begin euthanization if necessary. They also analyze the genomes of every avian influenza virus detected in the Fraser Valley to better understand how they are related, and how the virus is evolving.

“We can use that information to help our poultry producers understand their risk and how they can target their biosecurity,” Burns said.

So far, targeted biosecurity has not been enough to stop bird flu from finding its way into Fraser Valley farms—although it has helped.

The Krahn brothers use the same biosecurity measures as other local farmers. Their feed trucks arrive by appointment, washed and ready. They have barn-specific coveralls, boots, and gloves. And when their turkey farm was hit by avian influenza this past October, the sickness wasn’t coming from the doors.

“We didn’t see any sick birds” at the entryways and access points, James Krahn said. “We saw them near the ventilation points, exhaust fans, air intakes.”

It’s something Hall said many farmers have noticed: biosecurity measures seem to be keeping the virus from coming in through the doors. But Burns cautioned that anecdotal evidence isn’t enough on its own.

“At this time, it’s not entirely known how avian influenza gets from outside of a barn into a flock,” she said. “Probably on different farms, it happens different ways.

“Could it be brought in on someone’s boots? Certainly,” she continued. “Could it also be brought in on a feather floating in through an air intake valve from an infected wild bird? Probably also that. We need to do more research to further understand which of those risk pathways is most common.”

Some farmers, though, aren’t waiting for research to catch up with them.

Grassroots innovation

Infect me once, shame on you. Infect me twice, and it’s time to MacGyver a solution. That’s the approach many farmers are taking after a third wave of bird flu that just doesn’t seem to go away.

Dale Krahn said many farmers are looking at new ways to manage their ventilation fans, which help keep poultry barns at the right temperature and humidity level for chickens, but could potentially welcome in the virus from outside.

Some farmers have devised their own disinfection systems, hanging curtains over their intake vents and dripping a disinfecting solution on them. Some are trialling UV light filters, similar to the ones tested during the COVID-19 pandemic. Others are installing HEPA filters, which Krahn said is a “very, very expensive option.”

“But when it’s expensive, you start seeing how important it is,” Krahn said. “Even if it’s expensive to prevent the risk, the emotional toll [of potential infections] is pretty hard on … all of us.”

At the Krahns’ barns, they are considering whether to replace the vents with heat exchangers, which have a built-in filter that reduces the amount of air entering the barn while maintaining oxygen and humidity levels.

Officials in the government of Canada and BC’s Ministry of Agriculture aren’t jumping on the new technologies as quickly. But now that they understand how the virus is most commonly spread(tracking in mud and fecal matter, moving birds to a new flock) and how to reduce them (boot washes and quarantine), Burns said science can start tackling the next round of problems.

“We’re trying now just to start thinking about some of those things” farmers are beginning to implement, she said. “There may be an opportunity, given that we are on year three of this outbreak, to start to look at some of the more innovative technologies that we can add on to the highest biosecurity to reduce the risk even further.”

Some of that research is beginning—and will continue even as the most recent wave of avian influenza appears to be over. (Canada’s last documented case of bird flu in a commercial flock was on Feb. 28 in Ontario; BC hasn’t had an infection since Jan. 11.)

Burns’ staff and other researchers in Canada will continue to study lab work, analyze the effectiveness of bird flu policies in other countries, and re-examine how Canadian barns are built. The federal government has also purchased vaccines against avian influenza that can be given to people who are at the highest risk of becoming infected—likely poultry workers.

Amid the preparation in Canada’s avian influenza plans, there is also hope.

“What’s happened historically, until the last three years, is that the wild birds develop immunity to this strain of avian influenza,” Burns said. “They’ve done that with other strains in the past, and then they stopped carrying so much virus into the Fraser Valley and the pressure goes down to commercial poultry.

“So there’s a chance that nature may sort this out,” Burns continued. “But because it’s unknown, we still have to continue to do all this preparation work in parallel. We can’t just wait for nature to hopefully sort this out for us.”

Farmers feel the hope too, as they take a breather from the barrage of virus and wait for next fall’s outbreak to begin.

“I think the mood is different because we now have hope,” Dale Krahn said, looking back to 2004, when avian influenza first arrived, and to 2022 when the most recent ongoing outbreak began.

“We see science, and we see opportunities where we can actually invest and work towards solutions instead of dead ends.”