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/csels/dsepd/ss1978/lesson6/section1.html) and report your findings to her. Please note that we will not address all outbreak investigation steps in this assignment.
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. The report should be easy to follow and interpret and should be written as an academic paper in proper APA formatting. This paper should be 8-10 pages in length (not including the title page, abstract or references. The paper should also include properly formatted tables and graphs of the data you are given, as well as, the data you analyzed.
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/csels/dsepd/ss1978/lesson6/section2.html#step6)
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 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.
Expert Solution Preview
Introduction:
In this assignment, we will be investigating a potential outbreak of Salmonella at the Flinn Corporation. Using the data collected from the nurse’s interviews, we will analyze the symptoms exhibited by the employees and determine if they are consistent with Salmonellosis. Additionally, we will conduct descriptive epidemiology to identify trends and risk factors among the ill employees. Further, we will analyze the data from a retrospective cohort study to determine the most likely source of the illness. Based on our findings, we will provide recommendations for prevention and control measures to prevent future outbreaks in the cafeteria.
1. Do you think that an outbreak exists? Why would you recommend further investigation? Discuss your reasoning. (Step 2: Establish outbreak)
To determine if an outbreak exists, we need to evaluate if there is an increase in the number of sick employees compared to what is expected. The nurse has noticed an increase in the number of sick employees, suggesting a potential outbreak.
Further investigation is warranted due to several reasons:
– Increase in sick employees: The nurse’s observations of an increase in sick employees indicate a possible outbreak.
– Workplace setting: The employees work in the same corporation, which increases the likelihood of person-to-person transmission.
– Type of illness: If the symptoms reported by the employees are consistent with a specific disease, such as Salmonellosis, it strengthens the case for an outbreak.
– Potential public health implications: If an outbreak is confirmed, appropriate measures can be taken to prevent further transmission and protect public health.
Continued investigation is necessary to confirm the presence of an outbreak, identify the source, and implement control measures to curb the spread of the illness.
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)
Salmonellosis is an infectious disease caused by the bacterium Salmonella. It primarily affects the gastrointestinal tract, causing symptoms such as diarrhea, abdominal pain, fever, and nausea. According to research published in the Journal of Clinical Microbiology, the symptoms reported by the ill employees, including diarrhea and abdominal pain, are consistent with salmonellosis (Centers for Disease Control and Prevention, 2016).
The chain of infection for salmonellosis involves several key steps. Firstly, the bacteria must be present in the environment, such as contaminated food or water. Secondly, the bacteria must be ingested, usually by consuming contaminated food or water. Once ingested, the Salmonella bacteria can survive the acidic environment of the stomach and reach the small intestine. In the small intestine, the bacteria invade the intestinal cells and cause inflammation, leading to the symptoms of salmonellosis. The infected individuals then shed the bacteria in their feces, potentially contaminating the environment and perpetuating the cycle of infection (Scallan et al., 2011).
References:
Centers for Disease Control and Prevention. (2016). Salmonella infection (salmonellosis). Retrieved from https://www.cdc.gov/salmonella/index.html
Scallan, E., Hoekstra, R. M., Mahon, B. E., Jones, T. F., Griffin, P. M. (2011). An assessment of the human health impact of seven leading foodborne pathogens in the United States using disability-adjusted life years. Epidemiology and Infection, 139(5), 807-817.
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)
To determine the percentage of ill employees with each symptom, we will analyze the data from the Nurse’s Interview worksheet. By counting the number of ill employees with each symptom and dividing it by the total number of ill employees, we can calculate the percentage. For example, if there are 12 ill employees and 1 of them had blood in their stool, the percentage would be 8.3%.
By systematically analyzing the data, we can generate a comprehensive overview of the symptoms experienced by the ill employees and determine the most common symptoms associated with this outbreak.
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.
To determine the characteristics of the ill employees, we will analyze the data from the Nurse’s Interview worksheet. By counting the number of male and female ill employees and dividing it by the total number of ill employees, we can calculate the percentage of ill employees that are male or female. Additionally, by calculating the average age of the ill employees, we can determine the mean age.
b. Place – What percentage of ill employees ate at the cafeteria? What percentage of well employees ate at the cafeteria?
To determine the place characteristics, we will analyze the data from the Nurse’s Interview worksheet. By counting the number of ill employees who ate at the cafeteria and dividing it by the total number of ill employees, we can calculate the percentage of ill employees who ate at the cafeteria. Similarly, we can calculate the percentage of well employees who 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 the graph into your report. What type of epidemic curve is it? (Hint: read https://www.cdc.gov/csels/dsepd/ss1978/lesson6/section2.html#step6)
To analyze the time characteristics, we will utilize the data from the Nurse’s Interview worksheet and fill in the “# of cases” column in the “Epi Curve” worksheet. As we input the data, the graph will automatically generate. The appropriate title for the graph could be “Number of Salmonellosis Cases over Time at Flinn Corporation.”
Based on the shape of the generated epidemic curve, we can determine the type of epidemic it represents. Referring to the information provided in the provided CDC resource (https://www.cdc.gov/csels/dsepd/ss1978/lesson6/section2.html#step6), we will identify the curve as either common-source, propagated, or mixed.
5. Based on the information gathered, an hypothesis has been developed that a specific food item served at the cafeteria is causing the illness. A retrospective cohort study (Step 8) will be conducted to further test this hypothesis. Use the worksheet “Retrospective Cohort Study” to calculate attack rates and risk ratios. The first food item, Baked Chicken, is done for you. Report the risk ratio for each food item. Based on risk ratios, which food is most likely to be the source of the illness? Explain.
To test the hypothesis that a specific food item served at the cafeteria is causing the illness, we will conduct a retrospective cohort study using the data from the “Retrospective Cohort Study” worksheet. By calculating the attack rates and risk ratios for each food item, we can determine which food is most likely to be the source of the illness.
After calculating the risk ratios, we will compare them among different food items. The food item with the highest risk ratio indicates a higher likelihood of being the source of the illness. We will use this information to identify the food item most likely responsible for the outbreak.
6. Based on the findings, recommendations for prevention and control measures can be made. 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 the reference section.
To prevent future Salmonella outbreaks in the cafeteria, it is important to implement effective prevention and control measures based on food safety principles. Academic sources provide valuable insights into these measures. By referencing these sources, we can discuss the necessary preventive measures in detail, such as the importance of proper food handling, storage, and preparation, as well as regular hygiene practices among cafeteria staff.
By integrating the recommendations from academic sources, we can develop a comprehensive plan to improve food safety in the cafeteria and minimize the risk of Salmonella outbreaks. This will involve educating staff about food safety procedures, implementing regular inspections and audits, and ensuring proper sanitation practices are consistently followed.
Overall, the implementation of evidence-based preventive measures will be crucial in reducing the risk of Salmonella outbreaks and safeguarding the health of the employees at Flinn Corporation.
