Nova Scotia

New study sheds light on why cats can get COVID-19, but dogs can't

Cats can get COVID-19, but dogs can't, according to new research from Dalhousie University.

Dogs, bears, pigs, chickens and ducks all have mutation that stops them from getting coronavirus

Saby Mathavarajah, a PhD student at Dalhousie University in Halifax, was the lead author on the study. (CBC)

A new study is showing how COVID-19 may impact the rest of the animal kingdom.

Saby Mathavarajah is the lead author on the study and a PhD student at Dalhousie University in Halifax.

"We determined that along with cats, a number of different feline species — cheetahs, leopards, tigers and lions — are all predicted to be susceptible to the virus," he said.

Ferrets are also susceptible to the coronavirus, but not dogs, bears, pigs, chickens and ducks. 

"It turns out that a single amino acid [in the protein], which is what comprises a receptor, contributes to the susceptibility. That single change, or that single mutation, is what conferred resistance for dogs, for example, but not cats," Mathavarajah said. 

Zoos should pay attention

He pointed to the case of a tiger at a zoo in New York City testing positive for the coronavirus.

"If you're a zoo, thinking about this, maybe testing your animals, testing the people who work with these animals, and maybe restricting access. These are all ways we can protect the animals, as well as ourselves," he said. 

Cats can carry COVID-19, but it's not clear how big a role they play in spreading it. (Happy monkey/Shutterstock)

The tigers got sick from COVID-19, but domestic cats do not show any symptoms. Both can carry the coronavirus, which is found in respiratory droplets. 

Mathavarajah said it's not yet clear how big a factor cats play in spreading COVID-19, but testing for it in strays could help track the spread.

He said cat owners shouldn't worry about getting COVID-19 from their pets, but keeping them away from other cats and people would keep everyone safe.

Dr. Graham Dellaire, professor in pathology at Dalhousie, wrote the grants to the Natural Sciences and Engineering Research Council of Canada to fund the study. He also oversaw the research.

He said their labs have been shut since March and this was a good project to work on from home. The labs are slowly reopening.

Bats carry many diseases

He said better understanding how COVID-19 affects other animals can help us think about how it affects humans.

"Organisms have co-evolved with the pathogens that infect them. And so bats are very highly adapted to coronavirus, in fact many viruses," Dellaire said.

Dogs are not susceptible to COVID-19. (InBetweentheBlinks/Shutterstock)

"Bats carry Ebola, bats carry influenza, bats carry rabies. How can one organism be so resistant to being infected with so many different pathogens?"

Learning why can help us understand such ailments from a human perspective, he said.