From http://dmv.ca.gov/pubs/brochures/fast_facts/ffvr07.htm http://dmv.ca.gov/pubs/brochures/fast_facts/ffvr07.htm : "You may qualify for a DPplacard or DPplat

From http://dmv.ca.gov/pubs/brochures/fast_facts/ffvr07.htm http://dmv.ca.gov/pubs/brochures/fast_facts/ffvr07.htm : "You may qualify for a DPplacard or DPplates if you have impaired mobility due to having lost use of one or more lower extremities, or both hands, or have a diagnosed disease that substantially impairs or interferes with mobility, or one who is severely disabled to be unable to move without the aid of an assistive devise." So yes, illnesses can cause one to become disabled.