UK on alert after H5N1 bird flu spills over to sheep in world-first
The UK sheep had inflamed mammary gland much like infected cows in US.
The H5N1 bird flu has spilled over to a sheep for the first time, infecting a domesticated ruminant in the United Kingdom much like it has in US dairy cows, according to UK officials.
The single sheep—a ewe—in Yorkshire, England, was confirmed infected after captive birds on the same property had tested positive for the virus, according to an announcement Monday. The ewe's milk was found to be positive for the virus through a PCR test, which detected genetic signatures of the virus. The ewe also had H5 antibodies in its blood. At the time of the confirmation, the ewe had symptoms of the infection in the way of mastitis, inflammation of the mammary glands.
This mirrors what US dairy farmers have been seeing in cows. An outbreak of H5N1 in dairy cows erupted a year ago, on March 25, 2024. Since then, at least 989 herds across 17 states have been infected with bird flu. In previous reports, farmers and researchers have noted that the virus appears to attack the animal's mammary glands and their milk is teeming with the virus.
