The first known case in the US, of a pig with avian influenza or bird flu, has been confirmed by the US Department of Agriculture (USDA) at a small farm in Oregon.
The infection happened at a backyard farm where livestock were housed together and shared water sources and equipment. In other states, the combination has enabled transmission between species.
Although the five pigs present did not display signs of illness, the Oregon Department of Health and USDA ran tests.
The pigs were euthanised to facilitate additional diagnostic analysis. Test results were negative for two of the pigs, and test results are still pending for two others.
The farm has since been quarantined to prevent further spread of the virus. Other animals, including sheep and goats on the farm, remain under surveillance.
This farm is a non-commercial operation, and the animals were not intended for the commercial food supply. There is no concern about the safety of the nation’s pork supply as a result of this finding, the USDA has confirmed.
Bird flu
USDA’s National Veterinary Services Laboratories (NVSL) has conducted genomic sequencing of the virus from the poultry infected on this farm.
That sequencing has not identified any changes to the H5N1 virus that would suggest to USDA and Centers for Disease Control and Prevention (CDC) that it is more transmissible to humans. This indicates that the current risk to the public remains low.
USDA has since approved two vaccine field safety trials for vaccine candidates designed to protect dairy cows from H5N1, and continues to explore vaccine options for other species.
Updates will continue to be provided by local public health officials, Oregon Health Authority, Oregon State Veterinarian, Oregon Department of Agriculture, as well as the USDA and US Department of Health and Human Services.
The USDA has reminded all farmers that strong biosecurity is critical to eradicating the virus and to protecting the health of farmworkers, farmers and their families, livestock and businesses.