On 26 April, it emerged that mink on two mink farms in the province of Brabant had contracted the disease COVID-19. On 7 May two other mink farms in the Province of Brabant found infections. Wageningen Bioveterinary Research (WBVR) tested the animals and found that they were positive for coronavirus (SARS-CoV-2). Other animals, such as cats, may also be susceptible to this virus.
Below are frequently asked questions and answers about coronavirus in mink, the research currently being conducted and coronavirus in other kept animals.
- Symptoms of the disease and the infection of mink
- Research on coronavirus in mink
- Is there any danger to the environment?
- Other animals and coronavirus
- Handling my animals
1. Symptoms of the disease and the infection of mink
Some employees at the mink farms have had symptoms of COVID-19. It appears that the virus was introduced to the mink via these employees.
Only a few mink showed symptoms of the disease on the farms. The mink are kept in separate pens, which means that there is little to no contact between the animals. It appears to be an acute outbreak, where the farms quickly overcome the peak of the disease. The chance that mink will function as a reservoir of the virus appears to be small. Further research will be conducted into this.
The infected mink suffered from gastrointestinal complaints and respiratory problems. The mortality rate at the affected farms was also higher than usual.
Mink farmers are now obliged to report symptoms of COVID-19 (respiratory problems and increased mortality) to the national animal disease reporting centre of the Netherlands Food and Consumer Product Safety Authority (NVWA).
The Dutch Ministry of Agriculture, Nature and Food Quality (LNV) has also decided that mink are no longer allowed to be transported. The manure from these farms may no longer be removed either. The risks presented by the manure seem small but will be investigated further.
All Dutch mink farms will be screened and visitors are banned from visiting the stables.
Additional protection recommendations have been drawn up for mink farms where contamination with SARS-CoV-2 has been established.
Dutch researchers have shown that ferrets can infect each other via inhalation. Since mink are closely related to ferrets, it is possible that they can also transmit the virus to each other.
Pneumonia was seen in sections on mink and SARS-CoV-2 was detected in organs and throat swabs. Based on the variations in the genetic codes of the virus, it could be concluded that mink farms have transmitted the virus to each other.
Besides the infections found in the mink farms there are currently no known cases where coronavirus has been detected in farm animals. There are approximately 140 fur farms in the Netherlands. Now that mink appear to be susceptible to the virus, there is a chance that the virus will be found on more farms. Mink farmers are obliged to report this to the Netherlands Food and Consumer Product Safety Authority.
All Dutch mink farms will be screened and visitors are banned from visiting the stables.
2. Research on coronavirus in mink
Research is being conducted into the source of the infection and the transmission of the virus. It is important to know how the disease develops on the farm, as this provides knowledge about COVID-19 in animals and the transmission from human to animal and animal to animal.
Samples from sick animals are collected on the farms for testing. Samples from healthy animals are also collected for antibodies, so that it becomes clear whether animals without symptoms can also be infected. The research is a collaboration between Utrecht University (UU), GD Animal Health, Erasmus MC and Wageningen Bioveterinary Research (WBVR).
Furthermore, any cats on the farm will be included in the study, as felines are also susceptible to SARS-CoV-2. In three of the eleven cats, antibodies to COVID-19 have been demonstrated.
Although the virus is not expected to spread over long distances, air and dust samples were taken in the vicinity of the company as a precaution to see whether the virus is also present here. Research will also be conducted on the manure.
No virus was found in the air samples outside the farms. However, virus has been found in the immediate vicinity of mink on dust particles within the farms. It is not unknown that people can become infected with COVID-19 through these dust particles.
Source: Ministry of Agriculture, Nature and Food Quality (LNV)
The further research on mink farms will be carried out in accordance with internationally applicable standards. Research will be carried out with various institutes in the Netherlands, including Wageningen Bioveterinary Research, and also in cooperation with international partners when necessary.
3. Is there any danger to the environment?
It is plausible that the virus spreads in animals in the same way as it does between people via droplets in the air. All mink are housed indoors, making it unlikely that the virus will spread over greater distances.
As a precaution, air and dust samples were taken in the vicinity of the farm. The virus was not found in these samples. The advise not to cycle or walk within a radius of about 400 metres around the infected mink farms has therefore been withdrawn.
The outbreak is in the same area which experienced cases of Q fever and swine fever. Is this a coincidence?
4. Other animals and coronavirus
Mustelids, which include mink, are susceptible to infection with coronavirus, as these animals have specific receptors on their cells that are affected by the virus.
Felines, hamsters and monkeys are susceptible for the same reason, as are bats, from which the virus originates in China. For these animals, coronavirus can also be lethal, but the numbers are still small. Of the twenty or so infected cats worldwide, only one death has been reported.
There are a few cases of infected dogs worldwide, but they have few complaints.
The Ministry of Agriculture, Nature and Food Quality intends to investigate the extent to which coronavirus occurs in pigs, cats and mink. Animals will be tested as part of that research.
The reporting of animal diseases is only required for a limited number of animals, and there must be a special reason for this. Because other animals used in livestock farming do not appear to be sensitive to SARS-CoV-2, only mink are now subject to compulsory notification.
5. Handling my animals
As a precaution, animal keepers infected with coronavirus are advised to keep contact with animals to a minimum and to let others take care of them. This applies to pet owners, but also to livestock farmers.
Sick animals of patients infected with or with symptoms of COVID-19 should stay inside as much as possible. This also applies to cats, which may infect each other, just like the lions and tigers in a New York zoo. Keep your distance from animals that show symptoms of disease and wear gloves when changing the litter box.
If you suspect that an animal has COVID-19, we advise you to contact the veterinarian by telephone. The Netherlands Food and Consumer Product Safety Authority decides together with the veterinarian whether additional research is necessary. Wageningen Bioveterinary Research (WBVR) can test animals for the virus, but only in cases of risk and at the request of the Netherlands Food and Consumer Product Safety Authority.
Everywhere where people and animals live close together, there is a risk of zoonosis, so this also includes livestock and pets. The big difference between domesticated animals (both pets and livestock) and wild animals is that we have lived with the former for centuries and that a relatively limited number of animal species are involved. We have a great deal of knowledge about these animals and the pathogens they may be carrying. In addition, there are strict regulations and strict supervision of animal diseases with monitoring systems and, as soon as there are any signals, measures are taken, such as the outdoor ban on poultry in the event of avian influenza.
The coronavirus (SARS-CoV-2) that causes the disease COVID-19, is a virus that originates from wild animals. The number of species and the reservoir of potential pathogens is infinitely greater in wild animals, and we know much less about this. However, we are intervening in the habitat of wild animals in all kinds of ways, such as through mining and cutting down primeval forests, but aspects such as climate change also play a factor, as this causes animal habitats to shift. As a result, there are contacts between animals that previously did not come into contact with each other and people come into contact with animals with whom they previously had no contact. In Europe, for example, the risk of diseases transmitted by mosquitoes is increasing due to climate change.