Unknown 'Highly Contagious' Disease Kills 85 Wild Horses at Federal Facility in Colorado

Wild horses congregate on hillside above badlands
Wild horses congregate on hillside above badlands

Ascent/PKS Media Inc./Getty

An "unknown yet highly contagious and sometimes fatal disease" has killed at least 85 wild horses at a federal corral in Colorado, officials announced Wednesday.

The U.S. Bureau of Land Management (BLM) said the outbreak at the Cañon City facility first began on April 23. The facility is home to 2,550 horses. The facility animals impacted by the mysterious disease so far are the horses gathered from the West Douglas, Colorado area in fall 2021, according to a BLM news release.

Steven Hall, a spokesperson for BLM, told Reuters that the deceased horses are undergoing necropsies, and their blood and tissue samples are being analyzed at two university laboratories.

"The main symptoms seem to be respiratory issues and chest congestion," Hall added.

All infected animals have reportedly been placed in isolated areas away from healthy horses.

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The horse death toll increased since Monday when officials reported that 57 wild horses had died from the mysterious disease.

At the time, BLM said that the facility went under a voluntary quarantine.

"We are working with local, state, and federal officials to determine what is impacting horses in the facility and how we can respond as effectively as possible," Stephen Leonard, BLM Colorado Wild Horse and Burro Program Manager, said in the release.