An outbreak of gastroenteritis occurred in Bandar Tun Razak, a suburban neighborhood, on the evening of April 28. A total of 89 people went to the emergency departments of the three local hospitals during that evening. No more cases were reported afterward.

The patients complained of headache, fever, nausea, vomiting and diarrhea. The disease was severe enough in 19 patients to require hospitalization for rehydration.

The local health department was immediately notified of a potential food-borne outbreak of gastroenteritis in Bandar Tun Razak.

The epidemic team, including a medical epidemiologist (public health physician – Health Officer), health inspectors and a nurse, visited the local hospitals to interview the attending physicians, the patients and some of their relatives. Some stool samples were obtained from patients for microbiological identification of the causative agent.

The distribution of the disease by person (age and gender) was found as follows.

Therefore the epidemic team investigated the places where affected persons, their relatives and neighbors ate that day (April 28).

Once the implicated place was determined, the investigation centered on the food. The following table includes the food items served in that place on April 28:
None of the kitchen personnel were ill. The names of the kitchen personnel and their participation in the food preparation are as follows:
-Ms Mary prepared the beef rendang and the potatoes,
-Johan prepared the salad and the fruit cocktail,
-Salmah served all dishes except the ice cream, and
-Jamilah prepared the burgers and served the ice cream.
-The ice cream was a commercial brand and was bought at a nearby supermarket.

Given that the epidemic team worked fast enough and the implicated meal(s) was (were) identified before all food leftovers were discarded, food samples from some meal leftovers were taken to the laboratory. In addition, stool samples were taken from the kitchen personnel who prepared or handled each different food item.
The laboratory confirmed that Salmonella toxin was present in some of the food samples and that one of the kitchen personnel of that place had the same Salmonella species. Furthermore, the Salmonella species found in the food and the kitchen worker was the same species found in stool samples of the patients.