The SARS-CoV-2 virus and its numerable variants that cause COVID-19 had infected and killed millions of people across the globe. While the human population is believed to be the most vulnerable victim of the virus, the chances of other species like mammals and reptiles were not ruled out.

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Recent media reports of COVID-19 infection in cats, dogs, ferrets, monkeys, and most recently tigers have become a point of worry among scientists. Though, several studies suggest that the transmission of the virus in these species takes place from humans, what remains an imperative question is that why some animals despite human contact stay unscathed by the fury of coronavirus.

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Presence of spike protein

According to Linda Saif, a virologist and animal coronavirus expert at Ohio State University, the molecular compatibility between coronavirus and the species that it infects gives a way for the virus to accommodate into the cell. In other words, it becomes the factor the virus to break into the cell.

Unfortunately for humans and their close animal relatives, this entry factor becomes ‘spike protein’. While this protein is believed to be present in all vertebrates, the size of it makes all the difference.

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The size of ACE2, a point that binds to SARS-CoV-2’s spike protein is nearly or completely identical to the humans in domestic cats, dogs, and other primates, making them more vulnerable than other animals to COVID-19.

What animal can get infected with COVID-19?

Several experimental research suggested that various mammals including dogs, cats, ferrets, fruit bats, raccoon dogs, tree shrews, hamsters, mink, pigs and white-tailed deer can be infected with  SARS-CoV-2.

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Do they spread the virus?

According to the Centers for Disease Control and Prevention, experiments performed in laboratory settings indicated that certain animals like ferrets, fruit bats, hamsters, racoon dogs, and white-tailed deer can spread the infection to other animals of the same species. However, these observations were based on a small group of animals, and to get a clearer picture, more extensive researches will work.