Epidemiological investigation of an outbreak of food poisoning traced to yogurt among personnel of a military training center

ABSTRACT

A food borne outbreak is usually suspected when there is a history of ingestion of a common food, attack of several people simultaneously and similarity of signs and symptoms in the majority of cases. One such incidence happened in a military training centre where a lunch attended by 110 personnel was arranged. After about three hours, 57 of them reported sick to a local military hospital. A prospective study was performed to probe into the facts under which this outbreak erupted. A sample of 90 personnel who attended the lunch was interrogated for eating of food that was served. Mean age of the participants was 22 years while the range of incubation period was 3-5 hours. By examining the attack rates for consumers of various foods it was found that eating yogurt was significantly associated with the causing of outbreak. Exposure rates among those who ate yogurt was 94.7% P <0.001 while odds ratio showed [13.2] almost causative association. The epidemiological findings points out to the need of having check on the purchasing of food items from outside sources