(CNN)A gorilla at the San Diego Zoo Safari Park in California has recovered from Covid-19 after receiving monoclonal antibody therapy and other treatments.
Winston, an elderly silverback gorilla, and eight other gorilla troop members tested positive for the virus earlier this month after showing symptoms of "mild coughing, congestion, nasal discharge and intermittent lethargy," the zoo said. The gorillas were suspected to have been infected by an asymptomatic staff member.
Due to concerns over Winston's age and underlying medical conditions, veterinarians performed a diagnostic examination and were able to confirm he had pneumonia and heart disease, San Diego Zoo Safari Park said in a news release.
From a supply not permitted for human use, Winston received monoclonal antibody therapy, heart medications and antibiotics.
"Treatment with these synthetic versions of the body's natural defenses is thought to be effective in diminishing effects from the virus," the zoo said in its news release. "The veterinary team who treated Winston believe the antibodies may have contributed to his ability to overcome the virus."
Monoclonal antibody treatments that are used to treat humans have been shown to reduce viral load and lower a person's risk of hospitalization and even death. Unlike a vaccine that takes a few weeks to work, antibody treatments work right away.
With the help of veterinarians, wildlife care professionals and specialists, the entire troop is on track to make a full recovery.
"San Diego Zoo Global is relieved to announce that the eight-member troop is eating, drinking, interacting and on their way to a full recovery," the release read.
San Diego Zoo veterinarians have been working with specialists from around the world to secure a limited supply of vaccinations that are intended only for use on animals. Zoo officials have already begun to identify candidates for the spike protein vaccine at the San Diego Zoo and San Diego Zoo Safari Park.
San Diego Zoo Global said it "will continue to share what it has learned about curbing zoonotic disease transmission, biosecurity protocols in managed care and field settings, and the implications to ensuring optimal health outcomes for humans and wildlife globally."