Chinese researchers have found that cats can be infected by COVID-19, the disease caused by the new virus, and could spread it to other cats; however, dogs are not vulnerable to the infection.
The researchers from Harbin Veterinary Research Institute also said that chickens, ducks, and pigs are not likely to catch the coronavirus.
The findings are interesting but cat owners should not panic, said other scientists.
Virologist Dr. Linda Saif from the Ohio State University in Wooster said, “The results are based on lab experiments in which a small number of animals were deliberately given high doses of the virus, SARS-CoV-2, and do not represent real-life interactions between people and their pets.”
“There is no direct evidence that the infected cats secreted enough coronavirus to pass it on to people,” she added.
There have been a few reports of pets getting infected by the new coronavirus. One cat in Belgium and two dogs in Hong Kong have been reported to have the virus.
The researchers, who published their findings in bioRxiv, an open-access preprint repository for the biological sciences, wrote, “Cats and dogs are in close contact with humans, and therefore it is important to understand their susceptibility to SARS-CoV-2 for COVID-19 control.”
Lead researcher and virologist Zhigao Bu and team introduced samples of the virus into the noses of five domestic cats. Upon euthanizing two of the cats, the team found viral RNA and infectious virus particulates in their upper respiratory tract.
The other three cats were kept in cages with uninfected cats. The researchers then found viral RNA in of the exposed cats, suggesting that the transmission might have taken place through air droplets.
Dr. Saif said that infected cats were asymptomatic and one out of the three cats exposed to infected cats caught the virus. She said, “This suggests the virus may not be highly transmissible in cats.”
The researchers explained that the mode of transmission is unclear. That’s because the study did not describe how the cages were set up. They guess uninfected cats might have contracted the virus through contaminated urine or feces.
More studies are required to understand whether cats can pass the virus to other cats, explained Dr. Saif.
Epidemiologist Dirk Pfeiffer from the City University of Hong Kong said the findings suggest that cats must be considered in the effort to control the coronavirus but they are not a major factor in spreading the disease.
“The focus in the control of COVID-19 therefore undoubtedly needs to remain firmly on reducing the risk of human-to-human transmission,” said Pfeiffer.
Meanwhile, the U.S. Centers for Disease Control and Prevention (CDC) has recommended people with the coronavirus infection to limit close contact with their pets.
Dr. Saif said, “These are precautionary as would be advised for any new emerging disease where only limited information is available.”
The researchers, however, found that dogs were less susceptible to the coronavirus. They introduced the virus in five young dogs and found that two of them excreted viral RNA in their feces and none of them contained infectious virus particulates.
Similarly, pigs, chickens, and ducks had no viral RNA after the virus was introduced in them. The article originally appeared online on Nature.
