The UK and continental Europe have been hit by an "unprecedented" number of cases of bird flu this summer.
Almost 2,500 cases of the disease have been reported by poultry producers from all over the world since last year.
According to the latest update from the EU's European Centre for Disease Prevention and Control, there have been thousands of bird diseases recorded. Birds were killed by the virus on the north Atlantic coast.
Warmer weather and the end of migration by wild birds have led to a decline in the number of bird flu cases.
There has been an outbreak of bird flu in the UK and elsewhere in Europe this summer, leading to fears that the disease could become endemic in wild birds.
The number of birds that were affected by an outbreak was more than five times higher this year. The experts say that all kinds of birds have become sick.
Millions of poultry have been culled in the US and Canada as a result of the Atlantic Ocean outbreak.
Epidemics could get worse this winter, according to disease experts. As autumn migration begins and the number of wild birds wintering in Europe increases, they are likely to be at higher risk of HPAI.
In the UK and Europe, year-round infections could cause free-range chickens to be kept indoors.
There are questions about the effectiveness of vaccinations against bird flu and whether birds can still spread the disease if they are exposed to it.
Even if birds are kept inside, the European Commission wants eggs produced in the EU to be labeled as "free range".
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