U.K. officials on Thursday announced that poultry farmers were forced to kill 500,000 birds after a massive avian flu outbreak among poultry and other captive birds.
According to Christine Middlemiss, the chief veterinary officer, about 40 outbreaks have been confirmed by the government for avian flu so far this year. There were only 24 outbreaks for the entire 2020-21 bird flu season, which extends into spring.
Once the avian flu was confirmed among the poultry, farmers were ordered to kill all birds at that location to prevent the spread of the flu to remaining healthy animals.
Northern Ireland also experienced a considerable loss of livestock because of the avian flu. The Belfast Telegraph reported that some 22,000 ducks were culled after two flu cases were confirmed among people's flocks.
"This is now the largest outbreak of avian influenza on these islands," said Jim Blee, deputy director of the animal health and welfare division.
The flu has been affecting countries across Europe. Three cases of infections have been confirmed in Scotland, and three confirmed in Wales. Blee said Britain has reported more than 300 confirmed flu cases in wild birds.
"I'm very concerned about what's happening," Middlemiss told the BBC regarding the U.K. outbreak. "That's a really high number for the time of year for anything we've experienced before, and that's because of the high level of infection in the migratory wild birds. So it's really, really concerning because those birds will stay with us over the winter until early spring and the risk of infection remains."
U.K. authorities keep a close eye on avian flu cases around the world because it is spread by migrating birds and can be devastating to poultry producers. Experts estimate that outbreaks during the 2014-15 and 2016-17 seasons cost U.K. poultry producers about 125 million pounds ($165 million).
While the risk to humans is low, bird flu can affect people in rare cases.
To control the spread of the disease farmers have been ordered to keep all birds inside or under nets to stop them from coming in contact with wild fowl, and to implement strict hygiene measures.
While the number of birds culled so far this season sounds large, it is relatively small compared with the number of birds on U.K. poultry farms. Between the beginning of August and the end of October, poultry producers slaughtered about 20 million birds a week, according to the latest government statistics.
"In terms of food supply impact, it's actually a relatively small number," Middlemiss said of flu-related culling.
The situation in Britain is part of a larger trend across Europe, where authorities are seeing more frequent outbreaks of avian flu, Middlemiss said.
Although researchers don't know the reasons for the trend, one theory is that climate change has altered the migration patterns of wild birds, she said.
"The birds migrate to the north of Russia over the summer and mix with other birds and other global flight pathways there and they exchange the viruses, so it's quite plausible that with climate change and change in pathways different mixing is going on," Middlemiss said. "But that hasn't been fully investigated yet."
The Associated Press contributed to this report.
