Transmission of COVID-19 between two animals, specifically household pets of the same species, has been proven to be quite common.

A study conducted by the Harbin Veterinary Research Institute in China researched transmission of the virus between animals by administering a high dose of the virus to a group of cats and dogs and placing some of the infected animals next to uninfected control animals.

The study accomplished four major findings:

1. Immunity Increases by Age: Older animals had a stronger immune response to fight off the infection. The kittens who were administered the virus all became seriously ill, resulting in the death of two kittens. Meanwhile, the older cats were able to fight off the infection without becoming seriously ill.

2. Feline Susceptibility: Just after a week, one-third of the control cats were found positive for the virus, proving that the virus can replicate in cats and can transfer through respiratory droplets to other cats

3. Greater Resistance from Dogs: The dogs in the study were much resistant to the virus and did not transmit the virus to the other animals.

4. Unlikeliness of Transmission Across Species: The study found no evidence that would prove the inoculated dogs infected the control cats or the inoculated cats infected the control dogs.