At the beginning of September, the Finnish Food Authority will start monitoring avian influenza at all fur farms. In the first phase of monitoring, the occurrence of avian influenza virus in fur farm minks is investigated, as avian influenza infections in minks pose a greater risk to human health than avian influenza infections in foxes and raccoon dogs. Samples are taken at each of the approximately 130 mink farms in Finland.
Mink is a particularly problematic animal species in relation to avian influenza virus infections. Minks’ upper respiratory tracts contain receptors that can bind to both avian and human influenza viruses, which makes minks sensitive to infections caused by both types of influenza. Simultaneous infection of these viruses in a mink may result in a new mutant strain that may be more susceptible to human transmission.
The first phase of monitoring is expected to be completed by the end of October, after which monitoring and sampling will take place at fox and raccoon dog farms. Blood samples are taken at fur farms for antibody testing and animals that have died spontaneously or been put down are used to detect the virus. The samples are taken by municipal veterinarians and samplers authorised by the Finnish Food Authority. The samples are analysed in the Finnish Food Authority’s laboratory. The samples are also tested for the occurrence of coronavirus (SARS-CoV-2).
Infection found at 25 fur farms
The avian influenza epidemic began in Ostrobothnian fur farms in mid-July. The first infected fur farm was found in the Finnish Food Authority's laboratory tests on 13 July, and since then avian influenza infections have been confirmed at a total of 25 fur farms.
Farm-specific reports on the infection situation have been prepared for these farms and a total of some 120,000 animals have been ordered to be culled. So far, 13 farms have been issued a culling order, and one farm is still in the process of carrying out the order. All in all, Finland has around 400 fur farms with an estimated 1.3 million fur animals. After the skinning in the autumn, about 300,000 animals remain on the farms.
When managing an animal disease epidemic, the most important thing is to identify those animal farms that have infected animals. In animal disease monitoring, diseases are best found by examining diseased or newly dead animals, because they are most likely to have an active infection and the probability of also finding the cause of the disease is highest. Culling infected and exposed animals will reduce the infection pressure most effectively.
Monitoring of different animal diseases is ongoing at the Finnish Food Authority and the need to expand the monitoring programme will be assessed as necessary. With regard to avian influenza, it has been decided to investigate all fur farms.
More information:
Terhi Laaksonen, Director, tel. +358 29 520 4530 (Animal Health and Medication)
Research Professor Tuija Gadd, tel. +358 29 520 4183 (virological studies)
E-mail: firstname.lastname@ruokavirasto.fi