Prion diseases (CWD in deer, BSE in cattle, vCJD in humans) cross species barriers rarely but consequentially. The BSE-to-human jump in the 1990s proved species barriers can fail. Public health agencies treat CWD with appropriate caution while acknowledging there's no documented case of human infection.
Practical advice: test your deer in CWD zones, avoid eating positives, wear gloves when field-dressing, and minimize handling of nervous tissue. State disease risk pages cover local protocols.