Cougars in Yellowstone National Park in the United States are fighting a pandemic of their own.
For years now cougars have been getting infected with a bacteria known as Yersinia pestis.
It causes the disease plague, which takes three main forms: pneumonic, septicemic, and bubonic.
About 43% of the cougars studied faced Y. pestis infections.
The bacteria is similar to the Black Death, which spread across Europe and Asia in the mid-fourteenth century.
Y. pestis is a versatile killer. In addition to rodents and humans, it is known to have killed dogs, cats, camels, chickens, and pigs.
Two cases of pneumonic plague were diagnosed at a hospital in Beijing's Chaoyang district on 13 November 2019, prompting fears of an outbreak.
Doctors diagnosed a middle-aged man with fever, who had complained of difficulty breathing for some ten days, accompanied by his wife with similar symptoms.
Police quarantined the emergency room at the hospital and controls were placed on Chinese news aggregators.
On the 18th, a third case was reported in a 55-year-old male from Xilingol League, one of the twelve Mongolic autonomous regions in Northern China. The patient received treatment and 28 symptomless contacts were placed in quarantine.