Chinese Study Finds Cats Highly Susceptible to CCP Virus

WHO to investigate human-animal transmission

A cat waiting to be adopted looks out of its cage at the Royal Society for the Prevention of Cruelty to Animals Shelter and Veterinary Hospital in Sydney on April 1, 2020. Peter Parks/AFP via Getty Images

A study published in the American Association for the Advancement of Science on April 8 found that cats can become infected with the CCP virus, which has so far killed thousands of people around the world since it emerged in Wuhan, China, late last year.

The study, conducted by the People’s Republic of China and published in the journal Science, was aimed at identifying whether or not the virus could be transmitted to other animal species and in what way it behaves in other animals, as well as finding out which animals are most vulnerable to the virus so that they can be used to test experimental vaccines to fight it.

Based on research conducted in China in January and February, the study found ferrets can become infected with the CCP (Chinese Communist Party) virus—also known as the novel coronavirus—when researchers attempted to infect the animals by introducing viral particles via the nose.

However, the virus was found in the upper respiratory tract but did not cause severe disease.

They also found cats, aside from being highly susceptible to the virus, can also infect each other via respiratory droplets. Infected cats had virus in the mouth, nose, and small intestine. However, the study noted that researchers had “only collected feces from these cats and checked for viral RNA in their organs after euthanasia,” to avoid possible injury because the subadult cats had been “aggressive,” in their behavior.

Kittens exposed to the virus had massive lesions in their lungs, nose, and throat too, researchers said. “Surveillance for SARS-CoV-2 in cats should be considered as an adjunct to the elimination of COVID-19 in humans,” the authors wrote. Antibody tests showed dogs were less likely to catch the virus, while inoculated pigs, chickens, and ducks were not found to have any strain of the virus.

All experiments with infectious with SARS-CoV-2, the scientific term for the CCP virus, were performed in the biosafety level 4 and animal biosafety level 4 facilities in the Harbin Veterinary Research Institute of the Chinese Academy of Agricultural Sciences, and strict animal study and welfare protocols were followed, the authors said.

An earlier study published at the start of this month also found that cats can be infected with the CCP virus and can pass it on to other cats, but the study has not been peer-reviewed and experts cautioned that the work was done on a small number of lab animals infected with high doses of the virus.

A cat sleeps at the closed 2 Cats cat cafe in Seoul on April 2, 2020. Ed Jones/AFP via Getty Images

The latest study has prompted the World Health Organization (WHO) to say it will take a closer look at the transmission of the virus between humans and pets. The WHO is currently investigating several cases in which animals appear to have been infected with the CCP virus by their human caretakers, including that of a tiger in the United States who reportedly developed a dry cough and loss of appetite after contact with an infected zookeeper.

“We don’t believe that they are playing a role in transmission but we think that they may be able to be infected from an infected person,” Maria Van Kerkhove, the WHO’s technical lead on the outbreak, said during a press conference.

The Centers for Disease Control and Prevention also noted that it does not have any evidence that pets can spread the CCP virus, with Casey Barton Behravesh, director of the agency’s One Health Office in the National Center for Emerging and Zoonotic Infectious Diseases, telling Science that “there’s no reason to think pets might be a source of infection based on the information we have at this time.”

However, Daniel Kuritzkes, head of infectious diseases at Boston’s Brigham and Women’s Hospital, said the latest study comes as no surprise because in the “original SARS epidemic, civet cats were implicated as one of the vectors that may have transmitted the virus to humans.”

Kuritzkes added that the new data supports recommendations that “people who are with COVID-19 should be distancing themselves, not only from other household members but also from their household pets, so as not to transmit the virus to their pets, particularly to cats or other felines.”

Reuters contributed to this report.