United States: A sheep located in northern England became the initial recorded instance of H5N1 bird flu transmission to mammals worldwide according to British governmental findings. The newly discovered animal infection joins multiple cases of mammalian disease along with raising widespread pandemic concerns, as reported by Reuters.
Bird Flu’s Expanding Reach Among Mammals
The H5N1 virus strain has infected bears, cats, dairy cows, dogs, dolphins, seals and tigers across various worldwide locations. Researchers detected the UK case of bird flu through regular inspections of livestock on a Yorkshire farm which had previously identified viral particles in captive birds.
🇬🇧UK detects first case of bird flu in a sheep, stoking fears of spread
— NowCast (@Piyush_p77) March 24, 2025
Bird flu has been detected in a sheep in northern England, the first known case of its kind in the world, Britain's government said, adding to the growing list of mammals infected by the disease and fuelling… pic.twitter.com/jnTWxyOa3s
Sheep Infection Linked to Dairy Cow Outbreaks
The infected sheep, a ewe, was diagnosed with mastitis (inflammation of breast tissue) but showed no other symptoms. Tests detected bird flu in its milk, a pattern similar to the recent H5N1 outbreak in U.S. dairy cattle. The virus has continued to spread among American dairy cows since March 2024.
Veterinary officials culled the ewe, and no further infections were found in the rest of the flock.
No Evidence of Sheep-to-Sheep Transmission—Yet
As of now, scientists have found no evidence that the virus can spread between sheep. However, the UK government has expanded livestock monitoring in areas where captive birds were previously infected, following similar concerns raised in the United States, as reported by Reuters.
Expert Reassurance: Risk to Humans Remains Low
Dr. Meera Chand, emerging infection lead at the UK Health Security Agency, emphasized that the risk to humans is still minimal:
“Current evidence suggests that avian influenza viruses do not spread easily to people, and the risk of avian flu to the general public remains very low.”