Are Cats Resistant to SARS-CoV-2 Reinfection?

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The novel coronavirus is a zoonotic. For those who are unfamiliar, this means that it started out in animals before it made the jump over to humans, which is such a common scenario that about three out of every four infectious diseases that emerge in modern times can claim an animal origin. Naturally, if an infectious disease can jump from one species to another species, it stands to reason that it can jump to other species out there. As such, there are a lot of people out there who are concerned about the chances of the novel coronavirus spreading to cats. Some of them are concerned about the wellbeing of their pets. However, there are even more who are fearful of the infected cats spreading the novel coronavirus to humans, which would be one more complication in the struggle to bring the COVID-19 crisis under control. The whole situation isn’t helped by the paucity of knowledge because that can encourage interested individuals to imagine the worst.

Why Do People Believe that Cats Are Resistant to Reinfection By the Novel Coronavirus?

In any case, a paucity of knowledge isn’t the same as no knowledge whatsoever. Unsurprisingly, there are a lot of people who are concerned about the potential for cats as well as other animals to spread the novel coronavirus, meaning that there have been studies conducted into the matter. Much remains to be investigated and much remains to be confirmed, but there is some reason to believe that cats aren’t particularly dangerous as potential spreaders of the novel coronavirus.

For example, researchers at Colorado State University have carried out a study into the susceptibility of cats as well as dogs to being infected by the novel coronavirus. In short, they took seven adult cats as well as three adult dogs. After which, they infected three of the cats and three of the dogs with the novel coronavirus. Following 28 days, they re-infected the three cats with the novel coronavirus. Meanwhile, two of the remaining four cats were infected with the novel coronavirus. Soon enough, they were put in the same room as the remaining two cats.

None of the cats showed symptoms of COVID-19 such as coughing, sneezing, and breathing problems. However, the researchers managed to confirm viral shedding from the three infected cats following the initial exposure as well as a lack of viral shedding from the same three infected cats following the subsequent exposure. Meanwhile, the researchers managed to confirm viral shedding in the four remaining cats as well, though there was a gap because of the different times that the four remaining cats were exposed. As for the dogs, none of them showed any viral shedding whatsoever, which suggests that they are much more resistant to the novel coronavirus than cats.

There are a number of interesting thoughts about this. For example, the fact that the three infected cats showed no viral shedding with the subsequent exposure suggests that it is possible for those infected with the novel coronavirus to develop resistance to re-infection. Something that is very important because there has been some confusion over whether people can be re-infected or not, which has huge implications for the struggle to bring the COVID-19 crisis under control. Likewise, the fact that all four of the remaining cats became infected suggests that cats can have enough viral shedding to spread the novel coronavirus even when they are not showing visible symptoms. This is concerning because this raises the issue of whether it is possible for cats to spread the novel coronavirus to people. If so, that means that any plan to bring the COVID-19 crisis under control would be flawed without accounting for cats.

Having said this, it is important to note that this is just one study. In fact, this is one study that hasn’t been peer-reviewed, meaning that interested individuals should hesitate to draw too many conclusions at this point in time. Still, this study does seem to be in line with another study carried out by the Harbin Veterinary Research Institute, which also suggested that cats can be infected with the novel coronavirus as well as spreading the novel coronavirus to other cats.

Further Considerations

Ultimately, this is one more reminder that the COVID-19 crisis is far from being over. The novel coronavirus isn’t the most lethal pathogen that can be found out there. We don’t know its exact mortality rate because we don’t know the exact number of cases out there. However, there are numbers that range from the low single-digit percentages to less than one percent, which are still very bad but less so than, say, ebola with its approximately 50 percent mortality rate. Similarly, the novel coronavirus isn’t the most infectious pathogen that can be found out there. Currently, it seems to be as infectious as the seasonal flu, which is also very bad but less so than, say, something like the measles.

Unfortunately, COVID-19 has a number of factors that make the shutdown more than justified. For instance, it is a new disease, meaning that it can spread from person to person with minimal impediment because no one has a preexisting resistance to it. Combined with the fact that the novel coronavirus is found in the upper airway, this means the novel coronavirus can spread very fast when it is permitted to run wild without protective measures. By shutting down, governments can slow down the rate of infection, thus buying them valuable time in which to build up testing capabilities as well as treatment capabilities. Something that should make it much easier for them to handle both detected cases and undetected cases once everything opens back up.

Of course, victory over the novel coronavirus won’t be possible unless society has a good understanding of how it can and can’t be spread. After all, it is difficult for interested individuals to fend off something that they don’t even know is coming, which is why more research into this is needed. In the meantime, people who are concerned about their pets might want to follow the usual recommendations, which is to say, minimize close contact with others for the purpose of minimizing opportunities for the pathogen to jump from host to host.