COMMERCE CITY, Colo. (CBS4) – The Rocky Mountain Arsenal Wildlife Refuge will remain closed through at least Thursday because of the plague.

(credit: CBS)

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Officials had at least two confirmed cases in prairie dogs last week. The animals were infected by fleas.

(credit: CBS)

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The refuge has been spraying insecticide to try to keep it from spreading. Officials say they will evaluate the flea levels on Thursday and will then decide if they can reopen.

(credit: CBS)

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Health officials say there are no known human cases at this time, but if you think you may have been exposed, and have symptoms similar to the flu, you should consult a doctor.