WASHINGTON — Several Smithsonian National Zoo big cats have tested presumptive positive for the virus that causes COVID-19, zoo officials reported Friday.
Six African lions, a Sumatran tiger and two Amur tigers have tested presumptive positive, according to zoo officials. Final testing results are expected in the next few days.
Last weekend, animal keepers observed decreased appetites, coughing, sneezing and lethargy in several lions and tigers. All lions and tigers are being treated with anti-inflammatories and anti-nausea medication to address discomfort and decreased appetite. In addition, all are being treated with antibiotics for presumptive secondary bacterial pneumonia.
No animals at the zoo are showing any signs of infection.
The zoo said the public is not at risk because of the substantial distance between animals and visitors.
The Smithsonian National Zoo conducted an investigation to determine the source of the infection, but have not been able to pinpoint the source.
"While it is possible the infection was transmitted by an asymptomatic carrier, it has been standard practice for all animal care staff and essential staff to mask indoors in all public and non-public areas," the zoo said in a release Friday.
Lions are among the most susceptible to the virus that causes COVID-19.
Zoo workers in D.C. and Maryland are using a special COVID-19 vaccine specifically for zoo animals. The vaccine, made by a company called Zoetis, is composed in a similar way to the Johnson & Johnson vaccine. Both vaccines use disabled adenovirus that delivers instructions to the body on how to beat the coronavirus.
“This is vaccine technology that's been used before in animals and also in different species," Dr. Ellen Bronson, Director of Animal Health at the Maryland Zoo, said. "That's really important to us. That we know...we can expect it to be safe across the various species."
Vaccinations focus on three primary groups: primates, Felidaes [the cat family], and Mostelas [the weasel family].
“We know from the animals that have gotten natural infection that those were the most susceptible,” Bronson said.