Outbreak case study
Read through the three outbreak case studies given below and produce a report in which you should discuss each outbreak considering the following points:
1. What organism do you suspect has caused the outbreak and why? In your report you should consider the incubation period, what symptoms were reported, the foods involved and groups of population affected? Any other useful information of relevance. Note there may be more than one probable cause in some cases. Why have you ruled out certain organisms?
2. Which food is likely to be the source and why? You should consider the type of food and features of the suspected organism that make this food a more likely source.
3. What advice would you provide to the food handlers to prevent this type of outbreak from happening again?
4. If you feel that more than one organism could cause the symptoms described, explain what tests would you perform to confirm the identity of the causative agent and why?
Using the Harvard style of referencing, you should cite any external sources that you have used for information within the text and provide a reference list at the end of the report (this will not be considered as part of the word count).
When sourcing material to support your hypotheses, avoid using web-sites that do not contain peer-reviewed material such as WebMD, Wikipedia etc as you may be penalised. However, official web-sites such as government organisations (eg Public Health England, World Health Organisation, European Communicable Diseases Centre etc) containing verifiable data are acceptable.
On December 18th 1998, 115 people attended a traditional Christmas dinner of roast turkey and stuffing, potatoes, vegetables, gravy, Christmas pudding and ice cream in a community centre. Following the dinner, 86 (76%) of 113 people interviewed reported onset of illness characterized by diarrhoea (98%), abdominal cramps (71%), and vomiting (5%). The median incubation period was 4.5 hours (range: 2-11 hours). Duration of illness ranged from 1 hour to 4.5 days (mean duration 1.8 days); one person was hospitalized. The turkey was supplied to the venue frozen and had been commercially prepared. Thirteen pieces, weighing approximately 4.5 Kg each, had been cooked in an oven in four batches during December 17th – 18th. Cooked meat from the first three batches was stored in a home refrigerator; the last batch was taken directly to the event. Approximately 90 minutes before serving began, the meat was sliced and placed under heat lamps. The stuffing was prepared on the 18th from a commercially prepared, freeze-dried product that was reconstituted with water 2 hours before cooking. The potatoes and vegetables were peeled on the morning of the meal and cooked shortly before the meal commenced. The gravy was prepared on the 17th December using the juices from the turkey and thickened using a commercial thickening agent. It was stored in a domestic fridge and reheated just before the meal. The Christmas puddings were commercially produced and purchased 1 week before the meal. They were cooked by steaming for 3 hours prior to serving. The ice cream was purchased in 5 litre containers from a local supermarket 5 days before the meal and stored in a domestic freezer until the event.
End of case study details