Confirmed findings of influenza of avian origin in captive mammals
Updated 24 March 2025
Applies to England, Scotland and Wales
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Details of confirmed findings of influenza of avian origin in captive mammals in Great Britain (England, Scotland and Wales).
Sheep, March 2025
One domestic sheep (Ovis aries) tested positive for influenza of avian origin (H5N1) in March 2025. The case was identified following routine surveillance of farmed livestock on a premises in Yorkshire where highly pathogenic avian influenza (H5N1) had been confirmed in other captive birds. The single animal was a ewe with signs of mastitis but no other clinical signs. The milk was positive by polymerase chain reaction (PCR) and the blood tested positive for H5 antibodies. 聽
All affected birds and the infected ewe were humanely culled to mitigate the risk of further disease spread. Further official testing of the remaining flock of sheep were all negative for the presence of avian influenza virus.
South American bush dogs, March 2023
Ten South American bush dogs (Speothos venaticus venaticus) have tested positive for highly pathogenic avian influenza (H5N1) in March 2023.
These animals were part of a captive breeding programme at a zoological premises in England. They were tested as part of a routine investigation into an unusual mammal die-off in November 2022. Ten animals died or were euthanised in a group of 15 bush dogs, over a 9 day period.
The bush dogs had minimal clinical signs before death, and APHA cannot definitively state whether or not H5N1 caused the clinical signs. Influenza of avian origin was not suspected at the time; the virus has since been detected in postmortem samples.
There is no clear evidence suggesting mammal to mammal transmission. It is very likely all animals were exposed to the same source of infected wild birds.