Before revision: In epidemiology, sporadic is a term used to refer to a disease which occurs only infrequently, haphazardly, irregularly or occasionally from time to time in a few isolated places with no discernible temporal or spatial pattern, as opposed to a recognizable epidemic or endemic pattern.
After revision: In epidemiology, a sporadic disease is an infectious disease which occurs only infrequently, haphazardly, irregularly , or occasionally,,outbreak from time to time in a few isolated places with no discernible temporal or spatial pattern, as opposed to a recognizable epidemic or endemic pattern.