SAN DIEGO — A second snow leopard has tested positive for COVID-19 at the San Diego Zoo, just days after an earlier case, the organization said Thursday. Zoo staff tested stool samples from Naphisa, a 3-year-old female snow leopard, after she developed a cough “within the past few days,” according to a spokesperson. After the sample tested positive for the coronavirus in the zoo’s lab, the staff sent another sample to the California Animal Health and Food Safety Laboratory System; the state-level lab confirmed the result. That’s exactly what had happened July 23, when the zoo announced that Ramil, a 9-year-old male snow leopard, tested positive for the virus after keepers noticed he had a cough and runny nose.