Oswego Outbreak Case Study
When Dr. Rubin arrived in the field, he learned from the health officer that all persons known to be ill had attended a church supper held on the previous evening, April 18. Family members who did not attend the church supper did not become ill. Accordingly, Dr. Rubin focused the investigation on the supper. He completed interviews with 75 of the 80 persons known to have attended, collecting information about the occurrence and time of onset of symptoms, and foods consumed. Of the 75 persons interviewed, 46 persons reported gastrointestinal illness.
aureus.The ingredients used to prepare the ice cream were fresh, unpasteurized milk, condensed milk, sugar, eggs, flour, chocolate, and vanilla extract. The chocolate and vanilla mixes were prepared in separate containers on April 17, the day before the supper, and left covered overnight at room temperature before being frozen. The raw milk was an unlikely source of infection,because the chocolate ice cream was not contaminated.
The method of contamination of ice cream is not clearly understood. Whether the positive Staphylococcus nose and throat cultures occurring in the Petrie family had anything to do with the contamination is a matter of conjecture.
Friis, R. Sellers, T. (2014). Epidemiology for Public Health Practice. Jones and Bartlett Learning LLC. Pages 18, 20.
CDC Foodborne Outbreak Investigations (2012)
Field Epidemiology A Brief Overview (2010). Power Point Jones and Bartlett.