The first known case of avian influenza in a pig in the United States was confirmed at a small farm in Central Oregon on Wednesday.
The Oregon Department of Agriculture, along with the U.S. Department of Agriculture, confirmed at least one of five pigs at Crook County backyard farm tested positive for the H5N1 virus — the same strain that’s made its way across the country and has caused an outbreak in over 100 million poultry birds since 2022. Usually sick birds are euthanized to prevent them from entering the food supply.
USDA officials say the farm was noncommercial, and the animals were not intended to enter the commercial food supply. Officials say there is no concern about the safety of the nation’s pork. All five pigs, as well as 70 birds at the property that also tested positive for the virus last week, were euthanized, according to a statement from the Oregon Department of Agriculture.
“None of these animals that were affected on this farm or any of the farms in Oregon that have been infected have ever have ever entered the food supply,” said Dr. Ryan Scholz, Oregon’s state veterinarian. And our food does remain safe. Pork products remain safe. Meat products that are properly prepared remain safe. Eggs that are properly prepared, milk that’s been pasteurized that you can buy at the grocery store remains safe.
There are other animals like sheep and goats at the farm that officials are monitoring for symptoms of the virus.
Scholz said the virus is naturally present in migratory wild waterfowl, which is how it usually spreads to domestic animals.
“They [wild birds] serve as a reservoir for this virus,” he said. “So anytime we see concentrations of wild waterfowl moving through our state, particularly in the fall and then in the spring during migratory season, the risk of exposure of domestic poultry to this virus through intermingling with wild waterfowl, which is what we believe to happen on this farm, is much higher.”
Bird flu can spread to other wild and domestic animals
Unlike the name suggests, avian flu can jump to other animals, including wild mammals like seals, dolphins, mountain lions and grizzly bears. Earlier this year, scientists discovered the virus can jump to dairy cattle, though no cases have been reported in Oregon cattle. At least 14 states, including California and Idaho, have confirmed herds there have tested positive for the virus.
Avian influenza can be fatal to poultry birds like chicken, although health officials do emphasize the risk of bird flu in humans is low. But it is more likely to affect people who are in close, prolonged contact with sick animals.
“However, the risk remains low even in those settings, when appropriate personal protective equipment or PPE is used,” said Dr. Dean Sidelinger, the state state epidemiologist at the Oregon Health Authority.
There haven been over 40 outbreaks across backyard and commercial poultry farms in Oregon, where at least 127 people have been exposed to the virus, although to date, no one has reported becoming sick, according to Sidelinger.
“There have been no human H5N1 infections associated with outbreaks in Oregon. To date, no infections amongst people living in Oregon and no evidence of human-to-human transmission,” Sidelinger said. “With that, we can say that the risk of avian influenza to the general public remains low.”
Some scientists do warn that public health officials need to ramp up testing on farm workers exposed to sick animals or risk cases going undetected.
Oregon officials recently confirmed a case of avian influenza in poultry at a Clackamas County commercial egg farm. At least two farmworkers in southeast Washington tested positive for the virus after being in close contact with sick chickens at a commercial farm. Nearly 40 people across the country have tested positive for bird flu so far this year, according to the Centers for Disease Control and Prevention. Most have reported only mild symptoms, like eye redness.
Officials keeping an eye at the backyard farm
USDA officials have tested the virus found at the Crook County farm, and say it does not seem to have mutated or become more transmissible to people.
“USDA’s National Veterinary Services Laboratories has conducted genomic sequencing of virus from the poultry infected on this farm, and that sequencing has not identified any changes to the H5N1 virus that would suggest to USDA and CDC that it is more transmissible to humans, indicating that the current risk to the public remains low,” read a USDA statement.
ODA officials say the agency is coordinating with other state and federal agencies to implement a quarantine area at the farm, cleaning and disinfecting the area where the animals were and monitoring people who were exposed to the sick animals.
