BOZEMAN, Mont. (AP) — Yellowstone National Park officials say 16 employees tested positive for COVID-19 in September, marking a significant uptick in cases.

The Bozeman Daily Chronicle reports that the number of positive cases in September quadrupled from the number reported between May 18 and Aug. 30.

During that time, four park employees and one contractor tested positive for the virus and have since recovered.

Out of the estimated 2,000 Yellowstone employees, a total of .08% have tested positive for the virus.

Testing ramped up significantly in September.

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