Parkinson's disease has afflicted cats.
 During that time, it may be constantly present, or it may go into remission and periodically relapse
 For example, until the bacterial cause of tuberculosis was discovered in 1882, experts variously ascribed the disease to heredity, a sedentary lifestyle, depressed mood, and overindulgence in sex, rich food, or alcohol, all of which were social ills at the time

