Months away from when the pandemic started in the city of Wuhan, China, researchers are now getting a better idea of the implications of the novel coronavirus – not only for humans but also for pets.

A study by US and Japan researchers showed cats can become infected with SARS-CoV-2, the virus that causes COVID-19, and may be able to pass the virus to other cats. This challenges initial beliefs that pets weren’t exposed to the virus.

The team administrated three cats with the virus, which had been isolated from a human. They collected swab samples from their nose a day later and detected two of the three animals were positive with the virus. Three days later, all cats had the virus.

In order to investigate whether infected cats could pass the virus to other cats, they placed another group of three cats beside the cages, not administrating the virus to them directly. In six days, all of them were detected positive with the virus.

“That was a major finding for us — the cats did not have symptoms,” said Yoshihiro Kawaoka, who led the study. Kawaoka is also working with an international group of virologists to create a human COVID-19 vaccine called CoroFlu, now being tested.

The findings by Kawaoka and the group of researchers follows another study by China’s Academy of Agricultural Sciences, which had argued cats and ferrets could get infected and potentially transmit the virus.

The novel coronavirus is mainly transmitted by humans through contact with respiratory droplets and saliva. That’s why social distancing and the use of face masks have been suggested by experts as the main way of prevention, as well as staying at home as much as possible.

“It’s something for people to keep in mind,” said in a statement Peter Halfmann, a research professor and co-author. “If they are quarantined in their house and are worried about passing COVID-19 to children and spouses, they should also worry about giving it to their animals.”

There’s no evidence yet that cats can transmit the virus to humans, with no documented cases so far of humans getting the virus after being in touch with cats. Humans are still the biggest risk to other humans in the transmission of the virus.

Nevertheless, cases have been reported of cats getting infected after being in close contact with humans infected with the virus, as seen in the Bronx Zoo in New York City. That’s why the researchers suggest people that have symptoms of COVID-19 shouldn’t be in contact with cats.

“Animal welfare organizations are working very hard in this crisis to maintain the human-animal bond and keep pets with their people,” said Sandra Newbury, co-author. “It’s a stressful time for everyone, and now, more than ever, people need the comfort and support that pets provide.”

According to Ruthanne Chun, associate dean for clinical affairs at the University of Wisconsin Veterinary Care, if you have an indoor-pet that hasn’t been in touch with humans diagnosed positive with the virus then it’s safe to interact with the pet. But, if you have the virus, you should limit your interactions with your pet.

The study was published in the journal The New England Journal of Medicine.