Outbreak Investigation

On February 7, 2018, a nurse employed at the Flinn Corporation  noticed an increase in the number of employees who were sick. She was  concerned that there may be a Salmonella outbreak at the  company. She has interviewed each of the employees at the corporation.  She has taken samples and sent them out for testing but has not received  the results. She asks you, the local epidemiologist, to investigate to  see if an outbreak exists and if so what the source of the outbreak is.  You follow the Center for Disease Control and Prevention’s steps in  outbreak investigation https://www.cdc.gov/foodsafety/outbreaks/steps/detection.html)  and report your findings to her. Please note that we will not address  all outbreak investigation steps in this assignment.  Here is an  additional resource on epidemiology, https://www.cdc.gov/training/publichealth101/epidemiology.html 

Use the attached Excel worksheet to produce graphs and statistics to  answer the questions below. Submit your report as a Word doc and include  figures and tables you generate. 

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1. Look at the Excel Spreadsheet attached. There are 3 worksheets  (see tabs on bottom of page – “Nurse’s Interview”, “Epi Curve”,  “Retrospective Cohort Study”). The first sheet “Nurse’s Interview” has a  line list of employees who work at Flinn Corporation. This sheet  represents the data the nurse has collected from those employees in an  interview. Do you think that an outbreak exists? Why would you recommend  to further investigate? Discuss your reasoning. (Step 2: Establish  outbreak)

2. Research salmonellosis using academic sources. Are the symptoms  that the ill employees exhibit consistent with salmonellosis? Provide a  brief summary (1-2 paragraphs) of the disease and discuss the chain of  infection for this disease. Use in-text citations in proper APA format  and include all sources in your reference section. (Step 3: Verify  diagnosis)

3. Identify the percentage of ill employees with each symptom. For  example, 1 out of 12 ill employees had blood in stool (Bs) = 8.3%. (Step  4: Working case definition)

4. Conduct descriptive epidemiology (Step 6). Describe the  characteristics of the ill employees to determine trends and risk  factors.

a. Person – Calculate the percentage of ill employees that are male/female. Determine the mean age of the ill employees.

b. Place – What percentage of ill employees ate at the cafeteria? What percentage of well employees ate at the cafeteria?

c. Time – Using the data collected in the Nurse’s Interview, fill in  the column “# of cases” in the “Epi Curve” worksheet. Use 0 if there are  no cases. As you fill in the data, the graph will automatically  generate. Choose an appropriate title for the graph. Copy and paste  graph into your report. What type of epidemic curve is it ? (Hint: read https://www.cdc.gov/foodsafety/outbreaks/steps/detection.html)

5. Based on the information you have gathered, you have developed an  hypothesis that there is a food being served at the cafeteria that is  causing the employees to become ill. You need to further test this  hypothesis by conducting a retrospective cohort study (Step 8). Use the  worksheet “Retrospective Cohort Study” to calculate attack rates and  risk ratios. The first food item Baked Chicken is done for you. You can  also consult https://www.cdc.gov/foodsafety/outbreaks/steps/detection.html for  help. Report the Risk ratio for each food item. Based on risk ratios,  which is food is most likely to be the source of the illness? Explain.

6. Based on your findings, what would you recommend for prevention  and control measures? Apply food safety principles from academic sources  to discuss further prevention of Salmonella outbreaks in the cafeteria.  (Step 11) Use in-text citations and include sources in reference  section.