Fleas in Arizona test positive for plague

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TAYLOR, Ariz. — The infectious disease that killed millions during the Middle Ages has been found again in Arizona.

Fleas in Navajo County have tested positive for the plague, KTVK reported. One week ago, fleas on prairie dogs in Coconino County tested positive for the disease.

There are three types of plague that doctors can watch for: bubonic plague, septicemic plague and pneumonic plague. In all types, patients can have fever, headache, chills and weakness.

Properties are set to be treated and officials will monitor the region to see if they need to take additional steps.

, the plague is caused by Yersinia pestis.

For more on the specific symptoms, depending on the type of plague, click here.