The SARS-CoV-2 virus, which causes COVID, originated from bats and then, probably after passing through an intermediary host, gained the ability to infect humans.
Many new viruses that emerge in this way, like SARS-CoV-2, maintain the ability to infect both animals and humans.
It’s well documented the SARS-CoV-2 virus infects a number of different animals. Cases of COVID have been recorded in animals as different as hamsters, ferrets, lions, tigers, mink and non-human primates.
However the question that concerns many of us in our cosy domesticated worlds, is what sort of threat does the virus pose to cats and dogs, the animals we have the closest relationship with?
Can cats and dogs get COVID?
Yes, cats and dogs can get COVID.
Both cats and dogs have been found to have been infected with the virus. A number of studies that involved the testing of domestic pets have confirmed the presence of these infections.
One of the more interesting suggestions from a pre-print study (one that is yet to be reviewed by other scientists), is that cats and dogs were less susceptible to the BA.1 Omicron variant compared to previous variants.
It was speculated the mutations in this variant which we know made it more transmissible in humans may have made it less able to bind to cellular receptors in cats and dogs.
Who gives it to whom?
Although it’s theoretically possible for COVID to be transmitted in any direction – that is, from humans to cats and dogs, from cats and dogs to humans, and from these pets to each other – the current belief is the virus is primarily transmitted from humans to these pets.
There are a number of possible explanations for why transmission generally occurs in this direction.
However, the most likely explanation is that these animals, when infected, generate much lower viral loads than humans and they may shed the virus for only a short time, which makes them less likely to transmit the virus onwards.
How common is it in pets?
The question of how common COVID is in animals generally, and in domestic pets, is one being actively explored.
In terms of how common it is in cats and dogs, there are methodological challenges to answering this question in large studies. Try taking a nasal swab from your cat and see how this works out!
Despite the practical obstacles, a study published in June suggests these infections may be more common than initially thought. The researchers studied the blood samples of 59 dogs and 48 cats in Ontario, Canada, which lived with people who’d tested positive to COVID.
They found 52% of the cats, and 41% of the dogs, had antibodies targeted to SARS-CoV-2, suggesting they’d been previously infected with the coronavirus. Cats were more likely than dogs to have contracted COVID in this study, but the authors note there’s a lot of variability in the studies looking into the prevalence of infection in animals.
How severe is it in pets?
When a cat or dog gets COVID symptoms, they get pretty much the same symptoms as humans.
They generally don’t feel well and the symptoms they experience include coughing and sneezing, lethargy and loss of appetite.
But the good news is, available data suggests most of the time infection results in either no symptoms or very mild disease. And the duration of their symptoms, if they get them, may be very short.
Although it’s possible for a pet to get more severe symptoms, this seems to be uncommon.
So what should we make of this?
The strong message from what we know so far is that we humans pose much more of a threat to our cats and dogs than they pose to us when it comes to COVID.
Therefore, if you get infected it’s probably sensible to limit contact with your pets, particularly while you’re at your most infectious. Just like you probably do anyway, you should treat your pet as you would any other member of your family when you’re ill and do everything you can to reduce the likelihood of infecting them.
Trying to get your pet to wear a mask, however, is definitely a step too far…
The good news is that even if you were to give your pet COVID, chances are they will either get no symptoms or only mild symptoms. And even if they do experience more severe illness, the evidence suggests they will bounce back quickly.
Of course, if you do suspect your pet has COVID and you are unsure about what to do, you should seek professional advice.
The Conversation, 5 August 2022