The H5N1 bird flu virus has been detected in pigs in the United States for the first time

The H5N1 bird flu virus has been detected in pigs in the United States for the first time, raising concerns that the virus could infect humans and spread from person to person.

The U.S. Department of Agriculture said Wednesday (October 30) that a pig was found to be infected with the H5N1 bird flu virus at a farm in Oregon. H5N1 was previously confirmed in poultry at the farm.

At least two other pigs at the farm, where livestock and poultry share water, premises and equipment, have been tested for bird flu and authorities are awaiting the results, according to reports.

Pigs are considered hybrid vectors, in which both human and various animal influenza viruses can exchange genes. The concern is that this hybrid pathogen may have characteristics that make it easier to infect humans.

Veterinarians with the Oregon Department of Agriculture said the infection was caused by a strain circulating among wild birds. Oregon health officials say there is no indication the virus has been transmitted to humans.

The H5N1 bird flu virus has spread around the world in recent months, killing hundreds of millions of poultry and disrupting food supply chains. Large numbers of wild birds have also been killed by the virus and dozens of mammal species have been affected, raising concerns about the possibility of human infection.