The 10-year-olds identity has not been launched, however authorities state the death was caused from the bacterial illness.
Colorado authorities are examining the death of a child linked to the afflict.
The states Department of Public Health and Environment states the death comes as verified cases of the plague were confirmed in animals and fleas in at least six counties.
The Centers for Disease Control and Prevention states people can get the plague if they are bitten by rodents or animals who are infected.
10s of countless individuals in Europe died from the plague during the Middle Ages, but the CDC says now it can be treated with antibiotics if captured during the early phases.