OVER the past few weeks there has been ‘significant’ changes in the epidemiology of highly pathogenic H5 avian influenza in Europe.
HPAI H5N1 is spreading in wild birds, predominantly ducks, including Eurasian wigeon and mallard, along a migration flyway in northern Germany and Denmark.
See also: H5N1 avian influenza detected at Worcestershire wild bird rescue centre
“These species will migrate further west into GB, and many have already arrived, with high numbers of wigeon still expected across GB, peaking in December,” Defra’s most recent risk assessment, published on 26 October, suggests.
Some 300,000 wigeons overwinter in the UK at the peak.
“Whilst some birds have now arrived in GB, the majority will follow in the next few weeks, having flown through areas in northern Europe now reporting H5N1 HPAI.”
Rapidly changing situation
The previous Defra report made little mention of HPAI H5N1, demonstrating how much the situation has changed in a relatively short period.
This autumn, the first reported cases of H5N1 were in Barnacle geese in southern Finland in early September.
Defra suggests this detection could have represented the beginning of a new wave of HPAI spreading west in migratory waterfowl.
It has recently been detected in wild birds in Central Asia, southern Russia, Germany, Denmark, and the Netherlands.
Dutch housing order
The Dutch government imposed a housing order from 28 October after H5N1 was detected on an organic farm.
H5N1 has also recently been found on a small farm in Germany and two turkey farms in Italy.
As a result of the detection in the UK and the worsening situation in Europe, Defra has increased the risk of incursion of HPAI H5 via wild birds in Great Britain from LOW (event is rare but does occur) to MEDIUM (event occurs regularly).
The risk of poultry and captive bird exposure to HPAI H5 across the whole GB is still LOW (with MEDIUM uncertainty) where biosecurity is sub-optimal, and LOW (with LOW uncertainty) where stringent biosecurity measures are applied.