More than a dozen gorillas have tested positive for Covid-19 at Zoo Atlanta, USA, zoo officials said, The Guardian reported.

Staff were alerted when several of the zoo’s troop of 20 western lowland gorillas began exhibiting symptoms, including runny noses, mild coughing, and loss of appetite.

Fecal samples and swabs sent to the University of Georgia’s veterinary diagnostic laboratory showed that 13 of the great apes were positive for coronavirus, according to the Atlanta Journal-Constitution.

In a statement posted to the zoo’s website, officials said they believed a vaccinated member of its animal care team, who was wearing personal protective equipment and asymptomatic when she came to work, probably transmitted the virus.

“The teams are very closely monitoring the affected gorillas and are hopeful they will make a complete recovery,” Sam Rivera, Zoo Atlanta’s senior director of animal health, said.

Staff are paying close attention to Ozzie, a 60-year-old male gorilla thought to be most at risk of Covid complications.

As these gorillas recover, they will receive the Zoetis coronavirus vaccine developed for veterinary use.

Other animals at Zoo Atlanta that will receive the vaccine in the coming days will include Bornean and Sumatran orangutans, Sumatran tigers, African lions, and a clouded leopard.