As an epidemiologist from the Centers for Disease Control, youhave been asked to help a local health officer in the village ofSortumme. When you arrive in the village, the local health officerrelates the following story: Last night 46 people reported an acuteepisode of gastrointestinal illness characterized by nausea,vomiting, diarrhea, and abdominal pain. All 46 people say that theyattended the same church supper before becoming ill. Their familymembers who did not attend the supper did not become ill. A totalof 80 people were at the supper. You confirm the findings of thelocal health officer and suspect that something in the supper wasresponsible for all of these cases if illness. You also know fromrecent National Survey data that, on average, a person experiencesapproximately two episodes of acute gastro-intestinal illness peryear.
You learn that the supper was held in the basement of thevillage church and lasted from 6pm until 11pm. The food which wascontributed by members of the congregation, was spread out on atable and consumed throughout the evening. You are able tointerview 75 of the 80 people who attended the supper. Yourfindings on food and beverage consumption are detailed in theattached line listing, along with the time of onset of symptoms forpeople who became ill. Unfortunately, only about half of people whobecame ill reported the time they became eaten. Approximately 20%of those who became ill were treated by a doctor. No fecalspecimens were obtained for bacteriologic testing.
A. How many people were at risk for becoming ill?
B. What number will you use for the population at risk for thisstudy? Why does this number differ from the answer to question5?
C. As soon as the epidemiologist have the necessary data they plotan epidemic curve. How does the epidemic curve help in aninvestigation?
D. Using data from the attached line listing, graph the cases bytime of onset of illness to create an epidemic curve. Label theaxes and add an appropriate title.
