Other cats have tested positive for the virus, SARS-CoV-2, including a pet in Belgium and a tiger at the Bronx zoo. After the tiger who showed mild symptoms tested positive, the zoo collected fecal samples from other big cats and found that a total of five tigers and three lions had been infected. One of the tigers didn’t show any symptoms. All of the big cats are doing well, the zoo reported Wednesday.

In an experiment in China, cats were shown to be susceptible to infection with the coronavirus, showing mild symptoms. The researchers said the experiment also showed that cats could pass the virus to other cats. But that was in a laboratory setting. The virus was detected by tests done after the cats had been euthanized. The researchers noted in the paper, “It was difficult to perform regular nasal wash collection on the sub-adult cats because they were aggressive.”

The Agriculture Department and the C.D.C. emphasized that “there is no evidence that pets play a role in spreading the virus in the United States.” Other experts agree that people should not start looking at their cats with suspicion. If anything, it’s the other way around.

Karen Terio, the chief of the Zoological Pathology Program at University of Illinois’s veterinary college, where the Bronx Zoo tiger sample was tested, noted that hundreds of thousands of people have tested positive in the United States, as opposed to two cats.

Dr. Terio said that while the tests and the earlier experiments did show that cats appear to be somewhat susceptible to the virus, “If this was going to be a serious problem for cats, we would have seen greater numbers.” Either very few cats are being infected, or their symptoms are so mild that their owners don’t notice them or think they warrant a trip to the vet. The direction of infection “is not going to be cat to human,” she said. “It’s going to be us to our pets. Thankfully, they’re having very mild disease.”