DENVER (CBS4)– A woman visiting Colorado last month became infected with the bubonic plague, the latest in what the Centers for Disease Control and Prevention says is an unusually high number of human cases in the U.S.

The woman, from Michigan, was in Salida for the Gentlemen of the Road music festival the weekend of Aug. 21.

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“That individual did have travel history to Colorado within the incubation period,” said Dr. Jennifer House with the Colorado Department of Environmental Health.

(credit: CBS)

(credit: CBS)

The Michigan Department of Health and Human Services said Monday a Marquette County resident is recovering after being treated for the bubonic plague.

She mostly likely was infected while hiking the Methodist Mountain Trail System in Colorado.

She is one of 14 human cases reported across the country this year. For the past 40 years the majority of plague cases have been found in New Mexico, Arizona and Colorado.

The bubonic plague is a rare, life-threatening, flea-borne illness. It’s caused by bacteria occurring among wild rodents and their fleas in some areas of the western U.S.

According to the state health department, four human cases of the plague have been confirmed this year in the state.

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“Plague is in our environment, it’s been here for decades,” said House.

Two of those infected died, an unidentified adult in Pueblo County and a 16-year-old male from Larimer County who likely caught it from an infected flea while hiking.

Poudre High School baseball player Taylor Gaes, baseball player #22. (credit: Poudre baseball team)

Poudre High School baseball player Taylor Gaes, baseball player #22. (credit: Poudre baseball team)

Taylor Gaes died June 8 after coming down with what he thought was a bad case of the flu, but tests confirmed it was a rare form of the plague.

“It’s a very rare disease. We don’t see a lot of cases of it but unfortunately in individuals who get it usually get a very severe illness that could result in death,” said House.

Health experts recommend keeping animals on a leash and have those pets on flea medication to protect against the plague.

“So anything that puts you in the environment or your cat or dog out in the environment where they could pick up fleas, you could be at risk of acquiring the plauge,” said House.

Typically there are an average of seven cases of the plague in the U.S. each year. If detected early the plague can be treated with antibiotics.

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LINK: www.cdc.gov/plague