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Part 3 On the morning of March 11, the Texas Department of Health (TDH) in Austin received a telephone call from a student at a university in south-central Texas. The student reported that he and his roommate, a fraternity brother, were suffering from nausea, vomiting, and diarrhea. Both had become ill during the night. The roommate had taken an over-the-counter medication with some relief of his symptoms. Neither the student nor his roommate had seen a physician or gone to the emergency room. The students believed their illness was due to food they had eaten at a local pizzeria the previous night. They asked if they should attend classes and take a biology midterm exam that was scheduled that afternoon. TDH staff were skeptical of the student's report but felt that a minimal amount of exploration was necessary. They began by making a few telephone calls to establish the facts and determine if other persons were similarly affected. The pizzeria, where the student and his roommate had eaten, was closed until 11:00 A.M. There was no answer at the University Student Health Center, so a message was left on its answering machine. A call to the emergency room at a local hospital (Hospital A) revealed that 23 university students had been seen for acute gastroenteritis in the last 24 hours. In contrast, only three patients had been seen at the emergency room for similar symptoms from March 5-9, none of whom were associated with the university At 10:30 A.M., the physician from the University Student Health Center returned the call from TDH and reported that 20 students with vomiting and diarrhea had been seen the previous day. He believed only 1-2 students typically would have been seen for these symptoms in a week. The Health Center had not collected stool specimens from any of the ill students By March 12, seventy-five persons with vomiting or diarrhea had been reported to TDH. All were students who lived on the university campus. No cases were identified among university faculty or staff or from the local community. You, as the epidemiologist, hypothesize that foods purchased from the local pizzeria were contaminated and caused the outbreak. The initial student and his roommate both reported eating pizza and green leafy salad at the pizzeria, but other items on the menu include pasta salad, garlic bread, a meatball sub, and ice cream. How would you design an epidemiological investigation to research the cause of this outbreak? In 1-2 sentences each, provide the following study design parameters for the observational, analytic investigation that you will conduct to test your hypothesis. Justify your choices. [Design/Method Selection] 11. Observational study design type: 12. Description of study population: 13. Exposure definition (criteria for being considered exposed): 14 How exposure will be measured (data collection method): 15. Disease definition (criteria for being considered a case) 16. How disease will be measured (data collection method): 17 Analysis