At least two gorillas in the San Diego Zoo in California, USA have tested positive for COVID. This is the first known case of natural transmission to great apes, officials said as per a report in AFP.

They started to cough last week and were found to be COVID positive. Meanwhile, a third has symptoms, Governor Gavin Newsom said.

It is believed they got the virus from an asymptomatic zoo worker, though it’s not confirmed.

“Aside from some congestion and coughing, the gorillas are doing well,” the world-famous zoo’s executive director Lisa Peterson said in a statement.

“The troop remains quarantined together and are eating and drinking. We are hopeful for a full recovery,” she added.

Gorillas have 98% common DNA with humans, and studies show that some non-human primates are prone to being vulnerable to COVID.

It is unknown if the gorillas’ bodies will react badly to the disease or if others have been infected.

The San Diego Zoo Safari Park has been shut since early December due to a rise in cases. Workers have to wear PPE kits when near the gorillas, said the zoo.