Colorado squirrel tests positive for bubonic plague

In the midst of a COVID-19 pandemic, another infectious but rare disease has reared its ugly head—bubonic plague. A squirrel in Jefferson County, Colorado (just west of Denver) tested positive for the disease on Saturday, the first case of plague in the county since 2017, according to a statement released by Jefferson County Public Health (JCPH). The squirrel was tested after a citizen reported seeing more than a dozen dead squirrels in the area, according to the statement.

Caused by the bacteria Yersinia pestis, bubonic plague (the most common form of the disease) can be contracted by humans and household animals if proper precautions are not taken. The disease is infamous for killing about 25 million people in Europe during the Middle Ages. Worldwide, most cases occur in Asia and Africa. According to the Centers for Disease Control and Prevention, an average of seven cases of plague occur in humans each year. No statistics are available for the prevalence of plague in pets.

Cats are more susceptible to plague, and can die if not treated promptly with antibiotics, says JCPH. Cats can contract the illness from flea bites, a rodent scratch/bite, or rodent ingestion. Dogs are not as susceptible as cats but can contract the disease from plague-infected rodent fleas. Humans can be infected through flea bites, the cough of an infected animal, or by coming in direct contact with blood or tissue from an infected animal.

Dogs appear to be more resistant than cats to plague. Signs in cats may include fever, lethargy, inflammation of the lymph nodes below the lower jaw, a pus-like lesion along the jaw, lesions in the mouth, and cough. Symptoms in people are similar to those in cats and 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. Pet owners should contact their physician or veterinarian immediately if they or their pets display any signs of illness.

JCPH reassures the public that the risk of contracting the bubonic plague is extremely low, but appropriate precautions should be taken:

• Eliminate all sources of food, shelter and access for wild animals around the home.
• Do not feed wild animals.
• Maintain a litter-free yard to reduce wild animal habitats.
• Avoid contact with sick or dead wild animals and rodents.
• Use precaution when handling sick pets and have sick pets examined by a veterinarian.
• Consult with your veterinarian about flea and tick control for your pets, especially if you live near wild animal populations, such as prairie dog colonies or other known wildlife habitats.
• Keep pets from roaming freely outside the home where they may prey on wild animals and potentially bring the disease home.

According to the CDC, antibiotics are effective in treating plague. Without prompt treatment, however, the disease can cause serious illness or death.