In total 7 dead wild boar have washed ashore in recent days at the Danish island of Ærø. In the context of keeping Denmark free from African Swine Fever (ASF), the authorities disposed of the animals, but did not check for the virus.
The animals were found at different locations on the south coast of Ærø, confirmed Dr Stig Mellergaard, DVM, chief advisor at the Danish Ministry of Environment and Food. It is unlikely that the boar are of Danish origin, he told Pig Progress. He said, “We know that the Danish wild boar population, which is now 30-40 animals, is concentrated in the southern Jutland close to the Danish-German border. So it is unlikely that these drowned animals are Danish.”
A live wild boar photographed in Germany. Photo: Shutterstock
Dr Mellergaard said that it does happen once or twice a year that carcasses of wild boar wash ashore in Denmark, but that it is the first time this has happened at Ærø.
Spread of ASF in Eastern Europe
The findings are interesting in the context of the spread of African Swine Fever (ASF) in Middle and Eastern Europe, which is why several Danish and German media reported about the finding in recent days as well. Nevertheless, to put things into perspective, from Ærø to the nearest infected farm with ASF in northern Poland is over 600 km in a straight line (see below), so just factual data make it rather unlikely that ASF would have killed these animals.
In earlier reports in Danish and German media, Dr Mellergaard said it might have been a sow with her litter. Now the total has gone up to 7, Dr Mellergaard revised his opinion. He said, “If it was a sow with piglets we would expect that there might be 3 to 4 animals. With 7 animals it is more likely that it is a flock of wild boar that have been swimming out to an island along the Baltic Sea for foraging and they have been caught by the current and brought out to sea and drowned.”
The dead wild boar were collected by the Danish Emergency Management Agency and brought to rendering at the Danish rendering company Daka, Dr Mellergaard said.
No testing for ASF virus
Dr Mellergaard confirmed that the found carcasses are not tested for ASF virus. He said, “We test all dead and shot wild boar from Denmark (where we know the origin) in order to document that Denmark is free from ASF. However, testing of animals of unknown origin, has only academic interest and if the result of such a test, unexpectedly, should be positive for ASF, Denmark would have to report it to the OIE and it will be regarded as a Danish case. It will be very difficult to explain to the world that it, basically, is not a Danish case but reflects another country’s problem.”
New cases washing ashore will therefore be treated in a similar way, Dr Mellergaard said, as the animals are unlikely to be Danish. “Therefore, we have no intention of changing the procedure even if a number of animals would wash in at a later occasion.”