It was first identified in captive mule deer in Colorado. It's now spread to 23 states and two Canadian provinces. In 2012, it was detected in Texas mule deer.

Chronic Wasting Disease, or CWD, is a fatal neurological disorder that affects deer, elk and related species. While its origins are mysterious, it's among a class of disorders known as spongiform encephalopathies, which also includes BSE, or “mad cow disease.”

In our region, the disease is confined to deer in the Hueco Mountains, east of El Paso. It's not known to be transmissible to humans. But there's a statewide effort to monitor CWD – and to limit its spread.

In 1967, managers at a Colorado wildlife research facilit...