More than a dozen gorillas tested positive for COVID-19 at an Atlanta zoo

• Over a dozen gorillas at an Atlanta zoo tested positive for COVID-19.
• The gorillas were tested after showing symptoms, including coughing, nasal discharge, and changes in appetite.
• Some are being treated with monoclonal antibodies and officials are "hopeful they will make a complete recovery."

More than a dozen western lowland gorillas at a zoo in Atlanta have tested positive for COVID-19, officials at the facility said.

In total, at least 13 gorillas at Atlanta Zoo tested positive were diagnosed after exhibiting symptoms of the disease, including coughing, nasal discharge, and changes to their appetite, zoo officials said in a statement. Officials at the zoo took fecal and nasal samples, which were tested at the Athens Veterinary Diagnostic Laboratory, zoo officials added.

The Atlanta Journal-Constitution first reported the news.

"The teams are collecting samples for testing for the Zoo's entire gorilla population, which includes 20 members living in four troops, and will regularly test the gorillas regardless of the presence of symptoms," the zoo said in a statement.

Zoo Atlanta did not immediately return Insider's request for comment Sunday.

Dr. Sam Rivera, the senior director of animal health at Zoo Atlanta, told the AJC he believed the virus was first transmitted to the gorilla population by a vaccinated asymptomatic employee who cares for them. The worker was asymptomatic and wearing PPE but later tested positive, he said.

Zoo employees are not required to get the vaccine, though a high percentage of workers have been vaccinated, a zoo spokesperson told the AJC.

Zoo Atlanta said the infections occurred in an area of the facility with stringent COVID-19 safety precautions, but said it had instituted additional preventive measures, including such as N95 masks, Tyvek suits, modified cleaning protocols, and increased ventilation in the gorilla building.

After the gorillas recover from the disease, the zoo will vaccinate them using the Zoetis vaccine, a COVID-19 vaccine developed for use in animals, the Atlanta Zoo told the AJC. Zoo Atlanta has already vaccinated some of its species, including the Bornean and Sumatran orangutans, its Sumatran tigers, its African lions, and its clouded leopard, according to the AJC.

The gorillas at highest risk of serious complications are being treated with monoclonal antibodies, including 60-year-old Ozzie, who is showing mild symptoms of the disease, the Atlanta zoo told the AJC.

"The teams are very closely monitoring the affected gorillas and are hopeful they will make a complete recovery. They are receiving the best possible care, and we are prepared to provide additional supportive care should it become necessary," Rivera said.