Officials confirm human case of plague in Colorado

BSIP/Universal Images Group Editorial/Getty Images/File

Yersinia pestis, the bacterium responsible for plague, seen under an optical microscope.


A person in Pueblo County, Colorado, has been diagnosed with the plague, officials reported Tuesday.

The case was declared Friday based on preliminary test results and the possible source of the infection remains under investigation, the Pueblo Department of Public Health and Environment said in a news release.

Plague is an infectious disease caused by the bacterium Yersinia pestis, which is transmitted by fleas. Although the disease is best known for the “Black Death,” an outbreak that killed millions of Europeans in the Middle Ages, the bacteria circulates naturally among wild rodents and rarely infects humans today, according to the U.S. Centers for Disease Control and Prevention.

The plague is transmitted to humans through bites from infected fleas, contact with infected animals, or inhalation of cough droplets from an infected person or animal.

Anyone who develops symptoms of the plague should seek immediate medical attention, the CDC says. Typical symptoms include sudden fever and chills, severe headache, muscle aches, nausea, vomiting, and often swollen lymph nodes with pain.

“Plague can be successfully treated with antibiotics, but an infected person must be treated promptly to prevent serious complications or death,” Alicia Solis, program manager for the Office of Communicable Disease and Emergency Preparedness at the Pueblo Department of Public Health and Environment, said in the news release.

“We advise everyone to protect themselves and their pets from the plague,” the department said.

According to the ministry, one way to prevent infection is to remove places where wild rodents can roost near people, such as brush, piles of rocks, garbage and wood piles around homes, garages, sheds and recreation areas.

Get the weekly newsletter from CNN Health

Taking precautions around pets can also reduce the risk of transmission. The department advises treating dogs and cats for fleas, storing pet food in rodent-proof containers, and not allowing pets to roam in rodent-prone areas or sleep in your bed.

According to the CDC, there were 67 reported cases of plague in Colorado between 1970 and 2022. Worldwide, there were 3,248 human cases of plague reported between 2010 and 2015, most frequently in the Democratic Republic of Congo, Madagascar and Peru, the World Health Organization found.

“A plague vaccine is no longer available in the United States,” the CDC says. “New plague vaccines are in development but are not expected to be commercially available in the near future.”

Leave a Comment