Susceptibility to SARS-CoV-2 infection has been demonstrated in a wide range of mammals under laboratory conditions, with cats and ferrets being the most permissive hosts. Although transmission of SARS-CoV-2 occurs primarily between humans, there has been evidence of more than likely human-to-cat transmission, including transmission from infected owners of domestic cats.
About a case
On May 8, 2020, the Institute for Agrifood Research and Technology (IRTA) reported the case of the first cat infected by SARS-CoV-2 in Spain. It was about a cat who lived with a family affected by COVID-19. Coinciding with these events, the animal presented serious respiratory difficulties and was transferred to a veterinary hospital. The RT-PCR test confirmed that the animal had been infected with SARS-CoV-2, but with a very low residual viral load.
Few cases of feline SARS-CoV-2 infection have been reported worldwide to date, so the coronavirus research team at IRTA-CReSA, together with researchers from IrsiCaixa, the Barcelona Supercomputing Center (BSC) and veterinarians from a veterinary hospital near Barcelona have delved into the case study and it was published in the journal Proceedings of the National Academy of Sciences (PNAS). In this work, serological tests were carried out on the cat and on another cat that also lived in the same house, which did not present any signs of disease. Tests carried out show that both cats had developed antibodies against SARS-CoV-2.
Experimental studies that are currently being carried out show that cats, in addition to being infected with SARS-CoV-2, can transmit it to other nearby cats, but without any clinical signs. However, the researchers’ first suspicions were that both cats had been infected by their owners because they had not had contact with other cats. To verify this, the team analyzed the genetic sequence of the virus that the cat had and found that it was 99.9% similar to the virus of the owner who died. This fact suggests that the cat was directly infected from relatives.
Library prep kits for SARS-CoV-2 sequencing
Using a Swift kit, this research group was able to:
- Perform the sequencing of the complete genome of the virus in samples from the infected cat and its owner. The results confirmed the close genetic relationship between both samples (99.9% nucleotide identity).
- Detect mutations in the cat sequence that have not been previously detected in pets.
- Confirm previous observations of asymptomatic or mildly symptomatic SARS-CoV2 infection in cats, although it cannot be excluded that it may lead to serious disease.
In conclusion, these findings should encourage owners of COVID-19 positive cats to avoid close contact with their pets to prevent transmission of the virus. The World Organization for Animal Health (OIE) recommends that domestic cats in COVID-19 positive households should be quarantined as their owners, primarily for their welfare and not for public health concerns.
Reference: Joaquim Segalés, Mariona Puig, Jordi Rodon, Carlos Avila-Nieto, Jorge Carrillo, Guillermo Cantero, Maria Teresa Terrón, Sílvia Cruz, Mariona Parera, Marc Noguera-Julián, Nuria Izquierdo-Useros, Víctor Guallar, Enric Vidal, Alfonso Valencia, Ignacio Blanco, Julià Blanco, Bonaventura Clotet, Júlia Vergara-Alert. Detection of SARS-CoV-2 in a cat owned by a COVID-19−affected patient in Spain. Proceedings of the National Academy of Sciences. PNAS first published September 18, 2020. 202010817; DOI: 10.1073/pnas.2010817117