Coconino County officials are taking precautions after finding fleas collected in Picture Canyon northeast of Flagstaff have tested positive for plague.
The Arizona Daily Sun reported Friday that the County Public Health Services District is conducting additional tests and disinfecting prairie dog burrows.
Public health officials collected the fleas around trails in the popular hiking area after noticing some prairie dogs dying off.
The positive test is the first sign of plague activity in the county since last September in Doney Park.
Officials are advising residents to take precautions such as using insect repellent and to avoid handling sick or dead animals.
Symptoms of plague appear within two to six days after initial exposure. They can include fever, chills, swollen lymph glands and muscle pain.
Information from: Arizona Daily Sun, http://www.azdailysun.com/