SARS-CoV-2 infection in cats and dogs in infected mink farms.
Anna E van Aart1
Francisca C Velkers2
Egil A J Fischer2
Els M Broens3
Herman Egberink4
Shan Zhao4
Marc Engelsma5
Renate W Hakze-van der Honing5
Frank Harders5
Myrna M T de Rooij1
Carien Radstake6
Paola A Meijer2
Bas B Oude Munnink7
Jan de Rond8
Reina S Sikkema7
Arco N van der Spek9
Marcel Spierenburg9
Wendy J Wolters2
Robert-Jan Molenaar8
Marion P G Koopmans7
Wim H M van der Poel5
Arjan Stegeman2
Lidwien A M Smit1
Affiliations9 institutions
Institute for Risk Assessment Sciences (IRAS), Utrecht University, Utrecht, The Netherlands.
Faculty of Veterinary Medicine, Department of Farm Animal Health, Utrecht University, Utrecht, The Netherlands.
Department of Biomolecular Health Sciences, Infectious Diseases and Immunology, Clinical Infectiology Division, Utrecht University, Utrecht, The Netherlands.
Department of Biomolecular Health Sciences, Infectious Diseases and Immunology, Virology Division, Utrecht University, Utrecht, The Netherlands.
Wageningen Bioveterinary Research, Lelystad, The Netherlands.
Stichting Zwerfkatten Nederland (Stray Cat Foundation Netherlands), Nieuw Beijerland, The Netherlands.
Department of Viroscience, Erasmus MC, Rotterdam, The Netherlands.
GD Animal Health, Deventer, The Netherlands.
Netherlands Food and Consumer Product Safety Authority (NVWA), Utrecht, The Netherlands.
Animals like mink, cats and dogs are susceptible to SARS-CoV-2 infection. In the Netherlands, 69 out of 127 mink farms were infected with SARS-CoV-2 between April and November 2020 and all mink on infected farms were culled after SARS-CoV-2 infection to prevent further spread of the virus. On some farms, (feral) cats and dogs were present. This study provides insight into the prevalence of SARS-CoV-2-positive cats and dogs in 10 infected mink farms and their possible role in transmission of the virus. Throat and rectal swabs of 101 cats (12 domestic and 89 feral cats) and 13 dogs of 10 farms were tested for SARS-CoV-2 using PCR. Serological assays were performed on serum samples from 62 adult cats and all 13 dogs. Whole Genome Sequencing was performed on one cat sample. Cat-to-mink transmission parameters were estimated using data from all 10 farms. This study shows evidence of SARS-CoV-2 infection in 12 feral cats and 2 dogs. Eleven cats (18%) and two dogs (15%) tested serologically positive. Three feral cats (3%) and one dog (8%) tested PCR-positive. The sequence generated from the cat throat swab clustered with mink sequences from the same farm. The calculated rate of mink-to-cat transmission showed that cats on average had a chance of 12% (95%CI 10%-18%) of becoming infected by mink, assuming no cat-to-cat transmission. As only feral cats were infected it is most likely that infections in cats were initiated by mink, not by humans. Whether both dogs were infected by mink or humans remains inconclusive. This study presents one of the first reports of interspecies transmission of SARS-CoV-2 that does not involve humans, namely mink-to-cat transmission, which should also be considered as a potential risk for spread of SARS-CoV-2.
Serological assays were performed on serum samples from 62 adult cats and all 13 dogs. Eleven cats (18%) and two dogs (15%) tested serologically positive.
Method
serological assay
Sample type
serum
Serological EvidenceExtraction confidence 0.95
Key finding
Two dogs (15%) were serologically positive for SARS-CoV-2 antibodies on infected mink farms in the Netherlands.
Serological assays were performed on serum samples from 62 adult cats and all 13 dogs. Eleven cats (18%) and two dogs (15%) tested serologically positive.
Method
serological assay
Sample type
serum
Zoonotic Surveillance2 records
Zoonotic SurveillanceExtraction confidence 0.95
Key finding
PCR and serological surveillance of cats on SARS-CoV-2-infected mink farms in the Netherlands detected infection in feral cats, with 18% testing seropositive and 3% PCR-positive, indicating mink-to-cat transmission.
Throat and rectal swabs of 101 cats (12 domestic and 89 feral cats) and 13 dogs of 10 farms were tested for SARS-CoV-2 using PCR. Serological assays were performed on serum samples from 62 adult cats and all 13 dogs.
Method
PCR; serological assays
Sample type
throat swab; rectal swab; serum
Geographic raw
the Netherlands
Country inferred
Netherlands
Zoonotic SurveillanceExtraction confidence 0.90
Key finding
PCR and serological surveillance of dogs on SARS-CoV-2-infected mink farms in the Netherlands found two dogs seropositive and one PCR-positive, suggesting possible mink- or human-to-dog infections.
Throat and rectal swabs of 13 dogs of 10 farms were tested for SARS-CoV-2 using PCR. Serological assays were performed on serum samples from all 13 dogs.
Method
PCR; serological assays
Sample type
throat swab; rectal swab; serum
Geographic raw
the Netherlands
Country inferred
Netherlands
Cross Species Transmission1 records
Cross Species TransmissionExtraction confidence 0.98
Key finding
Evidence indicates mink-to-cat transmission of SARS-CoV-2 on mink farms in the Netherlands, representing animal-to-animal cross-species transmission.
The calculated rate of mink-to-cat transmission showed that cats on average had a chance of 12% (95%CI 10%-18%) of becoming infected by mink, assuming no cat-to-cat transmission. As only feral cats were infected it is most likely that infections in cats were initiated by mink, not by humans. This study presents one of the first reports of interspecies transmission of SARS-CoV-2 that does not involve humans, namely mink-to-cat transmission.
Method
PCR; serological assays; whole genome sequencing
Study design
field surveillance
Transmission direction
animal-to-animal
Geographic raw
Netherlands
Country inferred
Netherlands
Genomic Evolution1 records
Genomic EvolutionExtraction confidence 0.85
Key finding
A SARS-CoV-2 genome obtained from a cat clustered with mink sequences from the same farm, indicating close genetic relatedness and supporting mink-to-cat transmission.
Whole Genome Sequencing was performed on one cat sample. The sequence generated from the cat throat swab clustered with mink sequences from the same farm.
Genes or proteins
whole genome
Analysis methods
whole genome sequencing; phylogenetic analysis
Spillover Event1 records
Spillover EventExtraction confidence 0.90
Key finding
Evidence indicates mink-to-cat spillover of SARS-CoV-2 occurred on infected mink farms in the Netherlands.
The sequence generated from the cat throat swab clustered with mink sequences from the same farm. The calculated rate of mink-to-cat transmission showed that cats on average had a chance of 12% of becoming infected by mink.
Method
PCR; serological assay; whole genome sequencing
Study design
field surveillance
Transmission direction
animal-to-human
Geographic raw
Netherlands
Country inferred
Netherlands
Citation context
References
14 references
Reference network
Force-directed citation graph. OmniVira-indexed references are prioritized and recursively expanded up to three steps.
Serologic Screening of Severe Acute Respiratory Syndrome Coronavirus 2 Infection in Cats and Dogs during First Coronavirus Disease Wave, the Netherlands.
