Several gorillas at the San Diego Zoo Safari Park have tested positive for the virus that causes COVID-19 in what is believed to be the first known case of transmission to apes, San Diego Zoo Global (SDZG) announced on Monday.
Two of the gorillas from the animal park in North County San Diego began coughing on Wednesday, Jan. 6, leading veterinarians from the zoo to test fecal samples for the virus. The tests came back positive on Friday and were confirmed by the U.S Department of Agriculture's National Veterinary Services Laboratories on Monday.
"Research studies have verified that some non-human primates are susceptible to infection with SARS-CoV-2, but this is the first known instance of natural transmission to great apes and it is unknown if they will have any serious reaction," SDZG said.
California Gov. Gavin Newsom said two gorillas were positive and at least one other was symptomatic. The San Diego Zoo said the results "does not definitively rule out the presence of the virus in other members of the troop."
The park’s executive director, Lisa Peterson, told The Associated Press that eight gorillas that live together at the park are believed to have the virus and several have been coughing.
Zoo officials believe the gorillas contracted the virus from an asymptomatic staff member, despite the fact that staff members wear personal protective equipment when near the gorillas.
Newsom said more research is needed to confirm the source of the infection and the strain.
"There is some question: Did it come human-animal? That’s being determined and want us to respect that process," Newsom said. "But nonetheless, that’s long been a concern -- human to animal transmission -- but our beloved gorillas, obviously, we are concerned about."
The gorillas are being quarantined together and "are doing well," said Peterson, adding that the gorillas are eating and drinking.
According to the Centers for Disease Control, there is no evidence that animals play a significant role in spreading SARS-CoV-2 to people. The CDC is aware that the virus can spread from people to animals in some situations but says more research is needed.
The San Diego Zoo Safari Park has been fully closed to the public since Dec. 6 when a regional stay-at-home order went into effect based on ICU capacity The three-week order was extended indefinitely before Christmas.