A further four tigers and three lions have tested positive for coronavirus at the Bronx Zoo after a four-year-old Malaysian tiger contracted the disease earlier this month.
The Wildlife Conservation Society provided an update on the Nadia, the Malayan tiger and announced that seven more big cats have tested positive for Covid-19.
Vets confirmed Nadia had the disease after she and six other big cats fell ill at the New York zoo in what is believed to be the first known infection in an animal in the US or a tiger anywhere.
It is believed a zoo employee who was not yet showing symptoms had infected the animals.
A Wildlife Conservation Society (WCS) spokesperson said: "Subsequently, we can confirm that the three other tigers in Tiger Mountain and the three African lions that exhibited a cough have also tested positive for Covid-19.
"This testing was done by using a fecal sample test developed by our laboratory partners that does not require the animals to be placed under anaesthesia.
"The fecal tests confirmed our suspicion that all seven cats had the infection, and also determined that one tiger at Tiger Mountain that never developed a cough was also positive for the disease."
The nonprofit organisation which runs the zoo has now put preventive measures in place for all staff who are caring for the infected animals.
Bronx Zoo, which has been closed since March 16, said the animals are now behaving normally, eating well and are not coughing as much.
The news comes after two household cats from separate areas of New York tested positive for the coronavirus.
While other pets around the world have tested positive for Covid-19, scientists believe they cannot spread the disease to humans.
There have been a handful of reports outside the US of pet dogs or cats becoming infected after close contact with contagious people, including a Hong Kong dog that tested positive for a low level of the pathogen in February and early March.
Despite no evidence showing pets can transmit the disease to humans, the Centers for Disease Control and Prevention is still recommending people prevent their pets from interacting with people or animals outside their homes by keeping cats indoors and dogs out of dog parks, for example.
