SAN DIEGO (KSWB) — The Tiger Trail habitat at the San Diego Zoo Safari Park is closed after a group of Sumatran tigers is believed to have contracted the virus that causes COVID-19.

Some of the six tigers at the park were suffering from a cough, which led veterinarians to do an in-house SARS-CoV2 PCR test, a Safari Park spokesperson said. The test yielded a positive result from fecal samples and the Safari Park is now awaiting confirmation of the results by the National Veterinary Services Laboratory.

The tigers that may be infected were not showing concerning signs of illness other than the intermittent cough, fatigue and occasionally decreased appetite. None have required treatment.

The park said the Tiger Trail habitat will be closed until further notice as the tigers quarantine in their usual shared habitat.

“Our dedicated team of specialists will continue to provide the tigers the best care available – monitoring them closely and treating symptoms as they may arise,” the park spokesperson said. “This suspected exposure highlights the challenges of containing this virus.”

The tigers are the third species at the zoo or Safari Park who are believed to have been infected. The zoo said last week that a second snow leopard was suspected positive. How the snow leopards were exposed to the virus has not yet been revealed.

A troop of gorillas at the San Diego Zoo Safari Park made a full recovery after they tested positive for COVID-19 on Jan. 11.

The San Diego Zoo Wildlife Alliance said its staff has been working as fast as they can to vaccinate susceptible animals. A spokesperson said Tuesday that species at both parks have already had or are scheduled to receive their first vaccine in the coming days.