Since the beginning of the COVID-19 pandemic, some animals have tested positive for the virus.
This includes a small number of dogs and cats, as well as a tiger, lion and mink. This occurred after close contact with people with COVID-19.
Research has also shown that ferrets and cats can spread the infection to other animals of the same species in laboratory studies.
So, what is the latest research now telling us when it comes to mammals, pets and COVID-19 transmission?
Coronavirus generation in mammals
A machine-learning study was supported by the Biotechnology and Biological Sciences Research Council and the Medical Research Council (MRC).
The research from the University of Liverpool was published in Nature Communication. It suggests that the potential scale of novel coronavirus generation in wild and domestic animals is greater than thought.
Predicting which animals could be the source of a future coronavirus outbreak could guide approaches to reduce the risk of coronavirus emergence in animals and spill-over to human populations.
Potential animal hosts of coronaviruses
Dr Maya Wardeh from the University of Liverpool’s Institute of Infection, Veterinary and Ecological Sciences, said:
New coronaviruses can emerge when two different strains co-infect an animal, causing the viral genetic material to recombine.
The study suggests that there are:
- at least 11 times more associations between mammalian species and coronavirus strains than thought
- over 40 times more mammal species that can be infected with a diverse set of coronavirus strains than previously known
- other animals that could host coronaviruses, such as the dormitory camel, the African green monkey and the lesser Asiatic yellow bat.
What about pets?
It is rare, but it seems that humans can transmit coronavirus to their feline friends.
A University of Glasgow study identified two cases of human-to-cat COVID-19 transmission in the UK.
The team from the MRC-University of Glasgow Centre for Virus Research (CVR) published its findings in the Veterinary Record (BVA journals).
The cats were identified through a COVID-19 screening programme of the feline population in the UK. They were different breeds from separate households and initially displayed mild to severe respiratory signs.
No evidence of cat-to-human transmission
Through this recent CVR study, we know:
- at present, there is no evidence of cat-to-human transmission
- there is no evidence that cats, dogs or other domestic animals play any role in the epidemiology (the incidence and distribution) of human infections with SARS-CoV-2
- researchers found no evidence of species adaptation in the cat’s viral sequences.
Low risk to public health
So, what does all this mean to us when it comes to COVID-19 transmission?
Whether cats with COVID-19 could naturally transmit the virus to other animals, or back to humans, is so far unknown.
Professor Margaret Hosie from the MRC-University of Glasgow Centre for Virus Research, lead author of the CVR study, said:
Currently, animal-to-human transmission represents a relatively low risk to public health in areas where human-to-human transmission remains high.
However, as human cases decrease, the prospect of transmission among animals becomes increasingly important as a potential source of SARS-CoV-2 reintroduction to humans.
If animals become a reservoir for SARS-CoV-2, in which variants can develop and potentially subsequently transmit to humans, there are implications for vaccine escape.
These two cases of human-to-animal transmission found in the feline population in the UK, demonstrate why it is important that we improve our understanding of animal SARS-CoV-2 infection.
What other pets are affected?
There have been a few isolated reports of COVID-19 infection in dogs, but no systematic studies. The first confirmed case was that of a 17-year-old Pomeranian dog in Hong Kong.
To date, what we know is that COVID-19 infections have only been reported in:
There is no evidence yet that birds, including ducks and chickens, are susceptible to COVID-19 infection.
The factors that govern why one animal is susceptible to the new coronavirus while others are more resistant are unknown, but might reveal more about how this virus spreads and causes disease.
Professor Margaret Hosie said:
It is important to improve our understanding of whether exposed animals could play any role in transmission.
This means going forward, it is important to be continually informed and prepared.
Cats and COVID-19: what you can do
- the latest CVR study, as well as two previous studies demonstrate that cats are susceptible to SARS-CoV-2 infection
- cats are most likely to become infected from close interactions with infected people
- there are reports that some animals develop illness with symptoms of respiratory distress and diarrhoea that has cleared up
- to help prevent your cat from getting infected with coronavirus, the advice is to maintain good hygiene, including hand washing, while handling and interacting with your cat.
Last updated: 26 October 2021