Plague Reemerges in Colorado

Officials in southern Colorado have confirmed a case of the plague.

San Juan Basin Public Health (SJBPH) confirmed the case Monday in Archuleta County, a sparsely populated area along the state’s border with New Mexico. The unnamed person’s current condition is unclear.

“On behalf of all of us at SJBPH, our hearts go out to the family while we work with [state officials] to conduct a thorough investigation to keep residents safe,” Tiffany Switzer, Interim executive director of SJBPH, said in a statement. “While this disease is very rare, it is important to be aware of how you can be exposed and the symptoms it can cause. If you think you have symptoms consistent with plague, seek health care immediately and let them know you may have been exposed.”

The Centers for Disease Control and Prevention (CDC) reports nearly 500 confirmed cases of the plague between 1970 and 2020, and says around seven occur each year. These cases are largely clustered in the four corners area — where Colorado, New Mexico, Arizona and Utah meet — and scattered throughout California and the rest of the western U.S.

Around 80% of cases that appear in the United States are bubonic plague, also known as the Black Death — the deadly disease that killed somewhere between 30% and 60% of Europe’s population in the mid-1300s.

The World Health Organization reports that around 2,000 people will come down with the illness each year, usually in sparsely populated rural areas.

This is the second plague case recorded in southern Colorado this year, with a resident of nearby Montezuma County also coming down with a case.

Archuleta County officials warn that prairie dogs in the area are common carriers of the disease. 

“SJBPH investigates prairie dog population die-offs for the presence of plague. If an active colony of prairie dogs suddenly disappears, please report this to SJBPH. Residents should not eradicate or kill prairie dogs on their property as this increases the risk of exposure to plague-infested fleas,” the agency wrote.

The bacterial infection often jumps from rodents such as prairie dogs to fleas who bite the animal. Fleas can later pass the disease to humans they bite. The plague can also spread human-to-human via respiratory droplets in the air.