Officials from Jefferson County Public Health (JCPH) revealed that a squirrel in Morrison, Colorado—which is just west of Denver—tested positive for the plague.
"Plague is an infectious disease caused by the bacteria Yersinia pestis, and can be contracted by humans and household animals if proper precautions are not taken," the statement released by JCPH reads.
The concern is that people can contract the plague in various ways like bites from infected fleas, through the blood of an infected animal, or from a cough/bite from something that has the illness. Also, domesticated cats are at high risk of catching the plague because of the interactions they tend to have with rodents and illness-carrying fleas. This in turn could transmit the virus to the pets' owners. As a result, officials are urging people who believe their pet may have come in contact with the plague to inform their veterinarian immediately.
"All pet owners who live close to wild animal populations, such as prairie dog colonies or other known wildlife habitats, should consult their veterinarian about flea control for their pets to help prevent the transfer of fleas to humans," the statement continues while also detailing the symptoms of the plague.
"Symptoms of plague may include sudden onset of high fever, chills, headache, nausea and extreme pain and swelling of lymph nodes, occurring within two to seven days after exposure," the JCPH said. "Plague can be effectively treated with antibiotics when diagnosed early. Anyone experiencing these symptoms should consult a physician."
The risk of catching the plague is low as long as proper precautions are taken. Although it once killed 25 million people from 1346–1353, the bubonic plague is manageable with modern medicine. The CDC explains that a full round of antibiotics can cure a person of the plague in around 24 hours. Additionally, there are only about seven confirmed cases of the plague a year with an estimated mortality rate of 8-10%.