DENVER (CBS4)– Plague concerns have caused more closures in open space areas in the Denver metro area. Denver Parks and Rec crews have placed fencing around the entire First Creek Open Space.

(credit: CBS)

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Health officials first started closing off public areas last week due to prairie dogs with plague. Prairie dogs get the plague from infected fleas. Those fleas are killing the prairie dog colonies.

(credit: CBS)

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The fleas are bad for prairie dogs, but could also be threatening to family pets.

The Rocky Mountain Arsenal Wildlife Refuge was closed last week while they sprayed insecticide to kill the fleas.

(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.