They are hunted, fed and photographed. They cause motorists to swerve and gardeners to curse.

Whatever your interest in or aversion to white-tailed deer, you may eventually see fewer of them sprinting across the road, eating your cabbage or magnified in your rifle scope. The reason: chronic wasting disease, a fatal, incurable affliction that continues to spread in the mid-Atlantic.

Hunters and wildlife managers in the region can do little but slow the spread, hoping to head off the kind of scenario that has devastated deer populations in a few other states.

Though the number of deer found with CWD in the mid-Atlantic is relatively low so far—a total of 1,309 in Pennsylvania, Maryland, Virginia and West Virginia—the disease is expanding into new areas of each state. (New York found five CWD deer on a captive deer farm in 2005 but no infected deer have been found in the wild. CWD has not been found in Delaware.)

Pennsylvania, the state with the nation’s third-highest buck ki...