PPT Slide

Slightly more than half the children in the 1st and 2nd grade classes reported being ill. Although this seemed rather low, we found that only 33 of those children ate lunch prepared in the school cafeteria, the remaining 21 children had brought lunch from home. The attack rate in 1st and 2nd graders who ate lunch from the school cafeteria was 88%. The difference between illness rates among 1st and 2nd graders who ate school lunch and those who did not eat a school lunch

helped confirm our hypothesis of a foodborne cause and discredited an environmental source. The occurrence of illness among children in other classes was troublesome until we found that, for various reasons, these children all ate during the same period as the 1st and 2nd graders and did not eat with their regular classes. This added further support to a foodborne etiology. The short incubation period and predominance of vomiting suggested a Staphylococcus intoxication and we asked the laboratory test samples of the turkey and dressing for Staphylococcus. The fact that illness was limited to one lunch shift was troublesome and suggested that the causative agent was not equally distributed in the involved food.

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