A Bronx Zoo employee apparently sick with COVID-19 appears to have passed the virus to five big cats at the zoo in what is believed to be the first case of Human-to-Wild Animal transmission of COVID-19 in the U.S. As more is learned about this virus, this information is critical.

The role of veterinarians and animal hospitals across New York State and the country now appears critical as well as officials are asking anyone with an animal showing symptoms to contact their vets, and asking vets to work with state and federal animal safety offices. 

There still is no evidence of COVID-19 spreading from domestic companion animals to their humans, or vice versa, but advice from the CDC, and the US Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS.gov) continue to recommend that humans infected with COVID-19, either confirmed or suspected, should stay a safe distance from pets and other animals.

In the Wildlife Conservation Society‘s Bronx, New York City zoo, an employee working in the Tiger Mountain exhibit, in direct contact with tigers, lions, and other exotic big cats, was apparently infected with COVID-19 and then infected the animals while still asymptomatic. The zoo has been closed to the public since mid-March.

A total of five wild tigers and lions in the zoo then began showing symptoms of COVID-19 on March 27th, and one was chosen for sedation and testing. The test was performed by the USDA National Veterinary Services Laboratory and the positive result was confirmed by APHIS in a press release issued just hours ago.

This concerning development highlights how little is known about COVID-19 and its transmission among wildlife, livestock and pets around the world. Prior to this discovery, it was known only that the virus spread from wildlife-to-human in a Wuhan, China wet food market that trafficked in wild animals, and that other coronavirus strains have long been commonly known to exist in animals though they do not play a role in its spread to people or in the COVID-19 outbreak. The current worldwide pandemic is fueled instead by human-to-human spread. 

Every species of animal appears to react differently to the virus. A recent study out of China indicated that SARS-CoV-2, the coronavirus that causes COVID-19, can spread to cats and ferrets, but does not easily replicate in dogs, pigs, chickens, or ducks. None of these animals appear to play a role in transmission of the virus back to humans. More information is needed. 

The tigers and lions at the Bronx zoo are all expected to recover. New procedures are in place to protect all captive big cats at the four zoos operated by the Wildlife Conservation Society from the humans working there.