Bureau of Land Management (BLM) mustangs have so far been unaffected by the recent neurologic equine herpesvirus-1 (EHV-1) outbreak sweeping through Western states, according to a statement issued by the agency on May 26. The agency continues to monitor the outbreak, and has asked the public to contact local BLM offices about outbreak-related restrictions before bringing domestic horses onto agency-managed public lands.

According to the statement, the agency has been working with state and federal animal health officials to protect the mustangs and burros residing on the range and at BLM holding facilities from EHV-1 exposure. As of May 26, no BLM-managed wild horses or burros residing on the range or in holding facilities are known to be affected by the outbreak, the statement said.

In a May 25 letter, the Humane Society of the United States (HSUS) chief innovations officer Holly Hazard urged BLM Director Robert Abbey to "discourage … private horse owners from bringing potentially exposed domestic horses onto federal lands where they may contact and possibly infect wild horses or other equines."

In its statement the agency advised horse owners to consult with local BLM offices before bringing their horses onto public lands