what if a much deadlier coronavirus emerges in pets?

The recent suggestion that ministers may need to consider slaughtering or vaccinating animals to prevent the coronavirus from contracting another dangerous mutation and returning to humans may sound like a sudden panic, but it’s only part of a long debate among scientists.

Evidence that cats could be infected with SARS-CoV-2, the virus that causes COVID, emerged as early as April 2020 in Wuhan, China. Evidence that they could also transmit the infection to other cats under special conditions emerged the same month. Since then, infections have been confirmed in mink in Denmark and the Netherlands, in big cats in zoos, in dogs, ferrets and a range of other species. It should also be remembered that the source of SARS-CoV-2 is probably bats and other species of wildlife can also be infectable.

Infection of some of these species with SARS-CoV-2 can cause actual illness, creating veterinary, welfare or conservation problems. However, transmission to or from pets that spend a lot of time in close contact with humans also presents additional problems in trying to control a pandemic in humans. For example, if transmission between humans and cats occurs easily, controlling the pandemic in humans might require measures to prevent it, and this could include vaccinating and quarantining cats.

There is good evidence of transmission from humans to cats, but very little evidence of transmission from cats to humans. There is also not much evidence of cat-to-cat transmission in normal situations (i.e. not in a lab). At the moment, there is no reason to fear that infections in cats are a major problem. Your family and friends are much more exposed to COVID than their cats, although you should take the normal hygiene precautions you use to reduce the chances of catching other illnesses (such as toxoplasmosis) from cats.

There is currently no major risk associated with our companion cats and dogs that would justify specific control methods such as slaughter or quarantine. In the longer term, however, the emergence of new variants is cause for concern. These may be more easily transmitted (like the alpha variant) or more capable of infecting people who have been vaccinated or previously infected (like the beta variant). Variants may cause more severe illness, or they may cause less severe illness and look more like normal winter colds or flu.

It is almost inevitable that more of these variants will appear as the virus adapts to all of our attempts to control it. These new variants in people are quickly spotted in the UK as it implements the largest surveillance program in history. The long-term risk of SARS-CoV-2 in other species is that if the virus begins to circulate there, an even more unpleasant new variant could appear and not be recognized as a problem until it is. transmitted to humans.

While rare, the UK government needs to consider these possible future scenarios, and the possibility of new variants appearing in animals was part of the Scientific Advisory Group for Emergencies (Sage) recent report on the long-term course of SARS. -CoV. -2. The most important way to reduce the risk will be surveillance to identify any new variants in animals that have not yet appeared in humans. So don’t be surprised if your vet is asked to provide a swab sample from your pet if he exhibits respiratory symptoms – and you may also be asked to provide one yourself if this happens.

Mass vaccination of pets is unlikely

Vaccination of pets is much less likely. COVID vaccines for dogs and cats are in development, but it can be difficult to show they are effective.

The vaccines were only approved for use in humans after advanced stage human trials, where large numbers of people were vaccinated and followed to see if they were protected against infection. Even then, enough people in the trial must have been infected to demonstrate an effect of the COVID vaccine compared to the control vaccine. Performing similar trials in dogs and cats will be difficult when infection rates are low (or even unknown, as at present), and the smaller trials simply do not provide sufficient evidence.

It might be possible to use the same vaccines in cats and dogs as in humans, but this also poses a risk. It is now recognized that exposing vaccinated people to new infections may be a way to select for variants that may elude the immune response produced by the vaccine. If the same basic vaccine models are used in cats and dogs, it can select vaccine “escape variants” in those species, which can then be transferred even to vaccinated people. Especially if the vaccines have not been shown to be as effective as in humans, or if they are only given to certain cats and dogs.

Widespread euthanasia of pets as a precautionary measure (what would be called the “slaughter” of livestock or wildlife) is highly unlikely. Imagine the situation where a highly dangerous and potentially fatal variant spreads from a cat to its owner and family. Infection in people would ideally be contained by appropriate isolation in a suitable facility (as in the small number of Ebola cases in the UK), stopping the spread. Then the source cat and immediate cat contacts – if any – could be euthanized to reduce the immediate risk to humans and other cats.

Large-scale euthanasia of cats would make no sense unless the variant is already widespread. As long as surveillance for SARS-CoV-2 in humans and animals is in place to identify such a variant before it becomes dangerous, there is no point in worrying about the large-scale euthanasia of our pets.

Pet and wildlife monitoring programs are starting to be funded by government agencies, such as UK Research and Innovation. These agendas, and the continuation of the debate, will be essential to avoid misinformed overreactions in the future.