The UK and mainland Europe have been hit by an “unprecedented” number of bird flu cases this summer, with 47.5 million birds culled since last autumn, according to new figures.
Poultry producers from northern Norway’s Svalbard Islands to southern Portugal have collectively reported nearly 2,500 outbreaks of the disease since last year.
Thousands of outbreaks in wild birds have also been recorded, according to the latest EU update. European Center for Disease Prevention and Control. The virus reached seabird breeding colonies on the North Atlantic coast, killing large numbers.
In recent years, outbreaks of bird flu have decreased with warmer weather and the end of wild bird migration in the fall and winter.
But outbreaks continued in the UK and elsewhere in Europe this summer, raising fears that highly pathogenic variants of bird flu are now endemic in wild birds, creating a year-round risk of infection.
From June to September, the number of outbreaks in domesticated birds was more than five times higher than in the same period last year. Experts say that all kinds of bird species have now been infected, causing the virus to remain.
Outbreaks have also crossed the Atlantic Ocean, spreading from Europe to North America along migration routes and leading to the culling of millions of poultry in the US and Canada.
Disease experts say outbreaks could get even worse this winter.
“As autumn migration begins and the number of wild birds wintering in Europe increases, they are likely to be at increased risk of HPAI. [highly pathogenic avian influenza] infection than in previous years due to the observed persistence of the virus in Europe,” said Guilhem de Seze, head of risk assessment at the European Food Safety Authority.
Year-round infections in the UK and Europe could force free-range chickens to stay indoors.
Veterinary trials to evaluate bird flu vaccines have begun in France and the Netherlands, but there are questions about the efficacy of bird flu vaccines and whether vaccinated birds can still transmit the disease if infected.
The European Commission has said it wants to allow eggs produced in the EU to be labeled “free range”, even if the birds are kept indoors.
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