Food Poisoning Caused by Dried Bonito in a School Lunch Program

Abstract

Cabbage and carrot were boiled, cooled, and mixed with sliced dried bonito for a school lunch program in Kazo, Saitama, in October, 1969. Of 992 persons who had had lunch, 775 persons (78.1 %) were involved in food poisoning, manifesting fever, diarrhea, celialgia, vomiting, and headache. The incubation period ranged from 3 to 79 hours, mostly 25 hours.
Salmonella enteritidis was isolated from the feces of the patients, the preserred specimen of the lunch, and the remainder of dried bonito. It was presumed that the incriminated dried bonito might have been contaminated with 100, 000 to 1, 000, 000 Salmonella organisms per gram when served as lunch.