In a closed institution for children aged two to six years, convalescent from malnutrition and infectious disease, Shigella was present in 32.7% of the population. Acute diarrheal disease occurred at a rate of 235 cases per hundred children per year, the incidence being the same for children with and without Shigella.
Children with chronic recurrent shigellosis, typically persisting for weeks or even months, were revealed as a dangerous source of shigella infection. The data, though limited, indicate that the convalescent carrier state after ordinary acute diarrheal disease was brief, a matter of a few days. The healthy carrier state, under conditions of the study, was longer, 48 days in one instance, with an average of 17 days.
Chronic undifferentiated diarrheal disease, no Shigella present, was clinically indistinguishable from chronic recurring shigellosis and similarly for acute diarrheal disease. That a carrier state of undetermined nature also exists in undifferentiated diarrheal disease can be inferred from an epidemiological similarity.
Chief, Division of Microbiology, INCAP.
Physician, Servicio Especial de Salud Püblica (SESP), Guatemala.
Senior Lecturer (Epidemiology), Clinical Research Center, Department of Nutrition and Food Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, and Consultant to INCAP.