Colorado sees first human plague case since 2015: officials

A human has been infected with the bubonic plague for the first time in Colorado since 2015.

A resident from the southwestern part of the state was diagnosed with plague earlier this summer. He or she had exposure to infected squirrels, according to officials with the Colorado Department of Public Health and Environment.


“The patient had septicemic plague, which is in the blood and cannot be spread to other people. The resident recovered, and no other cases were identified,” officials said.

The news comes after a squirrel in Colorado recently tested positive for the bubonic plague. The squirrel is the first case of plague in the town of Morrison, located about 17 miles southwest of Denver.

“Plague is an infectious disease caused by the bacteria Yersinia pestis, and can be contracted by humans and household animals,” public health officials wrote in a statement. However, if proper precautions are taken, the risk of getting plague is “extremely low,” they added.

Humans can be infected through bites from infected fleas or animals.

Symptoms of plague can include high fever, chills, headache and nausea, among other signs, occurring within a week of exposure. However, plague can be treated with antibiotics upon early diagnosis.


“Plague has been present in Colorado since at least the 1940s, and cases in wild rodents in Colorado are reported most years,” said Dr. Jennifer House, state public health veterinarian, in a statement. “While we see most plague activity during the summer, the disease can be found in rodents year-round and sometimes spills over into other wildlife species as well as domestic cats and dogs.”

To protect against plague, health officials recommend the following precautions:

  • Do not directly handle any wildlife.
  • Keep pets away from wildlife, especially dead rodents and rabbits.
  • Don’t let dogs or cats hunt prairie dogs, other rodents, or rabbits.
  • Don’t allow pets to roam freely.
  • Treat all pets for fleas according to a veterinarian’s advice.
  • Do not feed wildlife – this attracts them to your property, brings them in close contact, and increases the risk of disease transmission.
  • Be aware of rodent and rabbit populations in your area, and report sudden die-offs or multiple dead animals to your local health department.