2005 electron microscopy image shows avian influenza A H5N1 virus particles. The U.S. Department of Agriculture announced Wednesday that pigs at an Oregon farm have been found to be infected with avian influenza. Cynthia Goldsmith, Jackie Katz/CDC/AP Hide Caption
Toggle caption Cynthia Goldsmith, Jackie Katz/CDC/AP
NEW YORK – The U.S. Department of Agriculture announced Wednesday that pigs at an Oregon farm have been found to be infected with avian influenza. It is the first time the virus has been detected in pigs in the United States, raising concerns about the potential for bird flu to pose a threat to humans.
The outbreak occurred at a backyard farm in Crook County in the central part of the state. There, various animals share water and are kept together. Last week, poultry at the farm was found to be infected with the virus, and testing this week revealed that one of the farm’s five pigs was infected.
The farm was isolated and all five pigs were euthanized to allow for further testing. This is not a commercial farm, and U.S. agriculture officials said there were no concerns about the safety of the domestic pork supply.
But Jennifer Nuzzo, a pandemic researcher at Brown University, said the discovery of avian influenza in swine raises concerns that the virus could be a stepping stone to becoming a bigger threat to people. Ta.
Pigs can be infected with multiple types of influenza, and pigs may play a role in making avian viruses better adapted to humans, she explained. Nuzzo pointed out that the 2009 H1N1 influenza pandemic was caused by pigs.
“To stay ahead of this virus and prevent it from becoming a threat to the wider public, it is critical to know whether the virus is present in pigs," Nuzzo said.
The USDA conducted genetic testing on the farm’s poultry and found no mutations that would suggest the virus has an increased ability to infect humans. Officials said this shows the current risk to the public remains low.
Another strain of avian influenza virus has been reported in pigs outside the United States in the past, but it has not caused a pandemic in humans.
“It’s not a one-on-one relationship where pigs get the virus and cause a pandemic,” said Troy Sutton, a Pennsylvania State University researcher who studies influenza viruses in animals.
This version of avian influenza, known as H5N1 type A, is widespread in wild birds, poultry, cattle, and many other animals in the United States. Its persistence makes people more likely to become infected and potentially infected, officials said.
Experts say the detection of infections in pigs is not necessarily surprising given that many other animals have been infected with the virus.
The Oregon pig outbreak is “notable, but does it change the threat level calculation? No, it doesn’t,” Sutton said. If the virus begins to spread more widely among pigs and then human infections occur, “then we will,” he said. I would be more worried. ”
So far this year, nearly 40 human cases have been reported in California, Colorado, Washington, Michigan, Texas, and Missouri, with most symptoms reported to be mild, such as red eyes. has been done. All but one had come into contact with infected animals.
