The disease, which is caused by the bacteria Yersinia pestis, can affect humans, household pets and wild animals alike.
Lawrence Stanberry, director of the programs in global health at Columbia University Vagelos College of Physicians and Surgeons in New York said that the chances of a squirrel being positive for the virus affecting humans would be very low.
"I've personally never even heard of a squirrel acquiring plague, but for (squirrels) to go on to be transmitters is extremely unlikely," he said. "And fortunately, we do have treatments for it these days, so (bubonic plague) is not the same scourge it was five or six centuries ago."
Stanberry said that other small animals, like prairie dogs, have been known to be affected by the bacteria in the past.
"Animals with a lot of time in the dirt are able to carry the pathogen," he explained.
According to the Jefferson County Health Department in Colorado, the largest risk to humans comes through bites from infected fleas, by cough from an infected animal, and through direct contact, such as a bite, with the blood or tissues of infected animals.
Some household pets are susceptible to the disease — cats are "highly susceptible," according to the health department. While dogs are "not as susceptible," they may "pick up and carry plague-infected rodent fleas." Pet owners who live close to wild animal populations should consult their veterinarian about flea control to prevent the transfer of fleas to humans.
If infected with the plague, symptoms will begin to appear within two to seven days of exposure. Symptoms include a sudden onset of high fever, chills, headache, nausea, and extreme pain and swelling of the lymph nodes.
However, the illness is treatable with antibiotics, especially when diagnosed early.
The health department stressed in a press release that the risk for getting plague is "extremely low" so long as precautions are taken, and recommends the following:
- Eliminate all sources of food, shelter and access for wild animals around the home.
- Do not feed wild animals.
- Maintain a litter and trash-free yard to reduce wild animal habitats.
- People and pets should avoid contact with sick or dead wild animals and rodents.
- Use precaution when handling sick pets. Have sick pets examined by a veterinarian.
- Consult with your veterinarian about flea and tick control for your pets.
- Keep pets from roaming freely outside the home where they may prey on wild animals and bring the disease home with them.