Plague case confirmed in Michigan

A Michigan resident has contracted the life-threatening bubonic plague — the first documented case in Michigan’s public health history, state officials confirmed.

The Marquette County adult is recovering after apparently contracting the rare flea-borne illness during a trip to Colorado. Officials are reassuring the public there is no cause for alarm, despite the disease's connection to the microorganism that caused the Black Death plague in Europe in the 1300s, killing millions and reshaping history.

"It’s the same organism but in this case, the infection resides in a lymph node," said Terry Frankovich, medical director for the Marquette County Health Department.

The bubonic plague is notably marked by one or more swollen, tender and painful lymph nodes, usually in the groin, armpit or neck.

With the bubonic plague, people are most often infected by bites from infected fleas or when they have direct contact with the tissues or body fluids from an infected animal. The highest risk is in settings that offer food and shelter for rodents — campsites and cabins, for example, according to the U.S. Centers for Disease Control & Prevention.

The Michigan resident's case did not develop into the more contagious pneumonic form of the plague. Pneumonic plague may be passed between humans, infecting the lungs and causing a rapidly developing pneumonia that can lead to respiratory failure and shock, according to the CDC.

A third form, septicemic, occurs when the plague organism multiplies in the blood, and it can lead to shock, organ failure and — as in the case of a Colorado teen earlier this year — death.

"Theoretically, the illness can move to bloodstream or to a lung infection, but this (Michigan) individual had localized infection, so there’s no concern about transmission," Frankovich said.

In fact, the adult is recovering after a hospitalization and diagnosis "within the past weeks." A lab confirmed the culture Monday, Frankovich said.

State officials echoed the reassurance.

In the Michigan case, “truly there is no risk to anyone,” said Jennifer Smith, a spokeswoman for the Michigan Department of Health and Human Services. “This is not something that occurs (in) Michigan. … This is a person who contracted this while they were away, and the individual is making a recovery and is not a public health (threat).”

The plague is rare, with an average of seven human cases reported across the U.S. each year, according to the CDC. However, the western U.S. is experiencing an increase in reported cases of plague in 2015, with 14 human cases, including four deaths reported.  

The reason for the increase is not known.