While people have been grappling with a deadly respiratory pandemic for the past three years, a fast-spreading strain of bird flu has largely flown under the radar. That is, until egg prices skyrocketed across the US, including in Colorado, and people wondered why. But the latest strain of highly pathogenic avian influenza is about much more than the eggs, it is deadly to birds.
“If we talk about the impact on domestic poultry, this virus causes almost 100 percent mortality in poultry flocks. We see this in backyard poultry stocks. You will die in a very short time. The birds get sick and they’re dying very quickly from this virus,” says Maggie Baldwin, the Colorado state veterinarian.
This strain of HPAI, which has been distributed in North America since late 2021 after arriving here from other continents, was first observed in Colorado in March 2022 in wild geese in the northeastern state. The first case of domestic birds was observed in April this year. From then until November 2022, HPAI fatalities were observed in raptors, waterfowl, and vultures statewide.
But since this bird flu spread across Colorado last year, up to 20 have been down in agriculture, according to the Colorado Department.
This type of devastation to commercial birds has caused egg prices to skyrocket across the country. It can be spread by a poultry worker stepping on infected goose droppings and dragging them into a barn. Or from small infected birds entering a poultry facility. Or even a migratory bird pooping on a facility as it flies over it.
The Colorado Department of Agriculture and the US Department of Agriculture are working together to manage situations involving a suspected outbreak of avian influenza at an egg production facility in Colorado. If there is a confirmed positive test for avian flu, all the birds in that facility must be beaten.
“We like to say depopulated or euthanized,” says Olga Robak, a spokeswoman for the CDA, noting that trade agreement protocols require the birds to be killed collectively to prevent the birds from likely dying anyway, preventing the virus from getting into invade the food system.
According to Baldwin, it is also about humane treatment of the birds, since the virus will almost certainly kill the animals.
“This virus causes systemic disease,” says Baldwin. “The most common clinical sign we see is sudden death. The most common thing we see is a bunch of birds dying at once.”
When the CDA learns of a possible case of bird flu, it sends a team to test the birds, whose samples are sent to an animal lab at Colorado State University. If the test is suspected to be positive, the sample is sent to a US Department of Agriculture laboratory in Iowa to confirm the test.
Sometimes euthanasia can wait until confirmed test results come back. But if the birds are all clearly dying or about to die, officials may choose to slaughter the birds before confirmed test results come back.
One way to deter the chickens is to pump carbon dioxide into their homes. Another involves pumping water-based foam into their barn, causing them to suffocate.
“If there is enough space on site, they can be buried. They can also be composted. Or they can be disposed of in either commercial or municipal waste. It really depends on the size of the farm what its facility looks like,” says Robak.
Bird flu hasn’t just hit chickens hard. Wild birds have also begun dying en masse in Colorado, including an incident in recent months in which over a thousand dead geese were found along a single reservoir in northeastern Colorado.
“Unlike previous strains of highly pathogenic avian influenza in North America, this particular strain causes widespread mortality in some species of wild birds, particularly snow geese, raptors and vultures. This phylum is also found in several species of mammals, particularly in skunks and foxes,” the Department of Colorado Parks & Wildlife notes on its website.
And the problem has reached cities too, leading to the Denver Department of Public Health & Environment sending out advice on Jan. 25 advising people not to touch or pick up a dead bird with their bare hands.
“As birds throughout Denver and much of the region are being impacted by highly pathogenic avian influenza, the Denver Department of Public Health & Environment (DDPHE) and Denver Parks & Recreation (DPR) are reminding residents that birds and wildlife can transmit diseases. Residents should never handle wildlife and should keep pets away from sick or dead birds,” said Tammy Vigil, a DDPHE spokeswoman.
According to Vigil, her department and Parks & Rec have received increasing calls from Denverans about “dead waterfowl,” most of which are geese, at certain city parks, including Town Center Park at Green Valley Ranch, as well as City Park and Washington Park, receive .
For dead birds in parks, residents should call 311 to report the deceased animals.
“If you find a dead bird on private property, you can dispose of the bird yourself, but avoid direct contact with the remains. Then call 311 to report it. If you don’t want to dispose of the bird yourself, you can call 311 to have it removed,” says Vigil.
And humans and their pet owners should also stay away from birds that appear ill, such as B. those who have symptoms such as tremors or lack of coordination, swelling around the head, neck and eyes, lack of energy or exercise, coughing, gasping for air, sneezing or diarrhea, according to Vigil.
And Parks & Rec is also advising residents against recovering dead geese on icy ponds or lakes in Denver.
“Don’t go on the ice to retrieve dead or sick geese. This is another reason to keep your pets on a leash — to avoid the risk of falling through the ice, as well as possible infection of your pet,” says Vigil.
The risk of bird-to-human transmission of avian flu is rare but can occur, typically when a person spends a lot of time with a dead bird or touches it and then touches its mouth, eyes or nose, DDPHE said.
According to Baldwin, there have been no “clinical human cases of avian influenza” in Colorado.
The risk of bird-to-pet transmission is also low, but the likelihood of transmission increases when a mammal eats an infected bird.
Also in Denver, a beloved murder of crows numbering in the tens of thousands who hang around the 1700 block of Grant Street in the evenings has also been stricken by bird flu. While these birds shit all over the sidewalk and parked cars, the most recent 311 complaints involved dead crows.
“These crows were tested for bird flu and they came back positive,” says Vigil.
The danger also extends beyond the crows in Denver.
Meanwhile, due to rising egg prices, some Denver residents have started buying chickens to hatch their own eggs.
“A lot of people don’t realize that highly pathogenic avian influenza poses a high risk to these birds,” notes Robak.
In fact, these birds get bird flu by being pooped out by birds flying overhead.
(Chain link alone won’t work) “We encourage people to keep their outdoor pets in a fine-meshed enclosure to prevent wild birds from ‘visiting,'” says Kenyon Moon, a Denver city bird expert, who adds this chain Link alone does not work. “Hard fiber on all six sides is ideal as it also keeps rats and mice away.”
Although Baldwin isn’t sure how bad the bird flu outbreak will be in Colorado, she believes there will be a spike in infections in the coming months as birds begin to migrate more. But there are biosecurity measures bird keepers can take, some of which are listed in the USDA’s Defend the Flock tool, that can mitigate the risk of bird flu.
“I think it’s important to share these tools with the bird-keeping public. Yes, that’s scary. Yes, this is worrying and worrying, and here’s what you can do about it. Here’s how you can protect your birds at home.” Baldwin says.