Epidemiological Analysis of an Outbreak

Each student will choose one of the following three case studies for their project. Each case study is accompanied by a Microsoft Excel datasheet that pertains to the case study.

Each student will use this data sheet to analyze data for their projects and will include it in their report.

Although the case studies are fictitious, they are very similar to actual outbreaks. The datasets provided are not actual data, but created for the sole purpose of this project.

For each case study the student will write a 5-8 page paper discussing the following aspects of the outbreak:

 Describe the organism responsible for the outbreak and any recent outbreaks this organism may have caused

 Describe the epidemiology of the organism (e.g., incubation period, modes of transmission, and common vehicles, susceptible populations, etc.)

 Outline a hypothesis on the source of an outbreak (given information on the organism, the descriptive epidemiology of cases and results of the interview)

 Please include a table of the following demographics and outbreak information for your cases: mean age, median age, percent female cases, percent male cases, average duration of illness, attack rate.

 Please include a bar graph of the symptom frequency

 Please include an epidemiology curve of your outbreak

 Interpret epidemiologic study findings (Odds Ratio and Confidence Interval)

 List the steps that might be used to investigate and address the public health problem

 Discuss what policies/procedures/recommendations are in place to prevent similar outbreaks (can be local, state, or federal policies)

 Note: Sources must be documented using MLA style

Introduction and Background: (Approximately 2 page)
This section should include research on the organism as epidemiology and outbreaks related to the organism.

Hypothesis: (1/2 page)
Please provide a hypothesis of what you think is the source of illness based on what you learned while researching the disease. Your hypothesis does not have to be the correct answer.

Data Analysis: (Approximately 1 page)
In this section please include your graphs/tables that you created in Microsoft Excel and your interpretation of each. All values should be calculated to 2 decimal places.
This section should include

 Table of demographics and outbreak information

 Graph of symptom frequency

 Epidemiologic curve

 Table of Odds Ratios

Discussion: (Approximately 1 page)
In this section please include steps involved in conducting this type of outbreak investigation (the case studies were intentionally vague).
Also include policies, procedures or recommendations that may be in place help prevent this type of outbreak.

Conclusion: (Approximately ½ page)
In this section you need to summarize your findings

Case Study #2: Clostridium perfringens at a BBQ Festival

On October 14, 2012 a hospital emergency room physicians called the Public Health Officer at an area health department stating that 11 individuals traveling by bus arrived at the emergency department with symptoms of severe abdominal cramping and
diarrhea.

Within an hour, an additional hospital called stating that they were treating 13 additional patients with the same symptoms. All patients reported leaving a BBQ festival and going straight to the hospital.
The Public Health Officer deploys an outbreak investigation team to interview the ill individuals.

Upon interview completion, the outbreak investigation team determines that all of the individuals attended the festival and ate a variety of different BBQ products.
In order to perform a case-control study, the investigation team retrieved credit card receipts from festival ticket sales and was able to contact more individuals who attended the festival.

They were able to obtain 64 complete interviews (31 interviews of ill individuals and 33 interviews for well individuals).
The outbreak investigation team was able to collect stool samples from patients at both hospitals. The public health laboratory was able to determine that the organism responsible for the outbreak was Clostridium perfringens.

By the time the outbreak investigation team arrived at the festival to collect food samples from the vendors, the festival was near its end and all food items had either been sold or were disposed of, therefore it was not possible to test food items for C perfringens.
Interview Responses were entered into a Microsoft Excel Database