The U.S. Department of Agriculture (USDA) reported on Wednesday that pigs in Oregon have been found to have the H5N1 avian influenza virus. This marks the first instance of the virus being detected in pigs within the United States.
While preliminary test results came back positive for some pigs, further testing is underway for two additional pigs at a farm in Crook County, Oregon, although two others tested negative. Remarkably, the pigs that tested positive exhibited no visible signs of illness.
According to officials, the pigs underwent testing for H5N1 due to precautionary measures taken because of the presence of the virus in other animals on the property.
This situation is alarming as pigs can be simultaneously infected with both avian and human viruses, which could lead to the emergence of mutant strains that might spread more easily to humans.
However, authorities have assured the public that there are no concerns regarding the safety of the domestic pork supply. This particular farm operates as a non-profit entity and is not part of the commercial food supply chain, as stated by the USDA. To curb the potential spread of the virus, the farm has been placed under quarantine, with other animals such as sheep and goats being monitored closely.
This news arrives amidst a broader outbreak of H5N1 that is affecting dairy cows nationwide. Reports from the Centers for Disease Control and Prevention (CDC) indicate that 387 herds across 14 states have been infected.
Since March, there have been 36 confirmed human cases, mainly involving individuals who had direct interaction with livestock or poultry, particularly in states like California and Colorado. Fortunately, all affected individuals have recovered, with symptoms primarily consisting of redness, eye discharge, and some mild respiratory issues.
There is currently no evidence suggesting that this strain of the virus has mutated in a manner that facilitates easier person-to-person transmission. The CDC confirmed last week that an extensive investigation found no proof of human-to-human transmission of the bird flu.
It remains uncertain how the pigs in Oregon contracted the virus, although state officials previously detected H5N1 in poultry on the same farm earlier this month. The livestock and poultry on the farm share essential resources like water, housing, and equipment, similar conditions in other states have allowed for interspecies transmission.
To ensure thorough understanding, the pigs that tested positive were euthanized for research purposes, to ascertain whether they were truly infected with H5N1 or merely exposed to particles of the virus. Michael Osterholm, an infectious disease authority and director at the Center for Infectious Disease Research and Policy at the University of Minnesota, noted, “This could be environmental contamination of the nose. I commend them for doing the autopsy. It’s really important to understand— is there evidence of actual infection?”
