DEFRA is closely monitoring outbreaks of highly pathogenic avian influenza in southern central Russia.
There have been 29 outbreaks in backyard flocks, one large poultry farm has been affected, and there have been two detections in wild birds.
The strain identified is a highly pathogenic H5N8 and has caused high mortality in domestic poultry.
It is not known if it is the same as the H5N8 strain that circulated in Europe last winter, which was the largest known HPAI outbreak on the continent.
The first detection of this latest cluster was on 28 July in a mixed flock of birds. More outbreaks were found through August.
A source said the outbreaks are all close to a large body of water populated by migrating waterfowl.
“But that does not mean they will be the same birds as arrive in the UK to overwinter and we don’t know if the wild bird population is immune from last year’s circulating viruses.”
Defra’s latest assessment suggests it is likely that the strain would be detected relatively quickly if it emerges in Europe this Autumn because of the high mortality associated with it.
It has not raised the risk level for the UK, which is currently considered low.
A spokesman at Defra said: “The UK retains its country free status for highly pathogenic avian influenza (HPAI), with no confirmed cases since June 2017.
“We are monitoring the situation carefully, and bird keepers should remain alert for any signs of disease, report suspected disease immediately and ensure they are maintaining good biosecurity on their premises.”