The role of preschool children and day-care centers in the spread of shigellosis in urban communities.

Shigellosis epidemics were investigated in two urban centers. In each city, preschool children played a major role in O!fecting their families and were most susceptible to secondary infection after illness had been introduced into the household. Children attending day-care centers were significantly more likely to be initial cases and to be the major cause of intrafamilial spread of disease than were their counterparts who did not leave the home for daytime care. This study suggests that day-care centers may play an important role in the transmission of shigellosis in urban communities.