Using your own words, give a definition of epidemiology.

Study Questions and Exercises

1. Using your own words, give a definition of epidemiology.
2. Before you read Chapter 1, what were your impressions regarding the scope of epidemiology? Based on the material presented in this chapter, what topics are covered by epidemiology? That is, to what extent does epidemiology focus exclusively on the study of infectious diseases or on other types of diseases and conditions?
3. How would the clinical and epidemiologic descriptions of disease differ, and how would they be similar? Relate epidemiology to the term population medicine.
4. To what extent does epidemiology rely on medical disciplines for its content, and to what extent does it draw on other disciplines? Explain the statement that epidemiology is interdisciplinary.
5. Describe the significance for the epidemiology of the following historical developments:

• associating the environment with disease causality use of vital statistics use of natural experiments identification of specific agents of disease

Explain what is meant by the following components of the definition of epidemiology:

• determinants
• distribution
• morbidity and mortality

6) The following questions pertain to the term epidemic.

• What is meant by an epidemic? Give a definition in your own words.
• Describe a scenario in which only one or two cases of disease may represent an epidemic.
• What is the purpose of surveillance?
• Give an example of a disease that has cyclic patterns.
• What is the epidemic threshold for a disease? In what sense is it possible to conceive of the epidemic threshold as a statistical concept?

8)During the next week, read and review health-related articles available on the Internet or in your local or national newspaper. Try to find the following terms used in newspaper articles; keep a record of them and describe how they are used:

• epidemiology
• epidemiologist
• infectious disease
• chronic disease
• clinical trial
• increased risk of mortality associated with a new medication

9)

10) Review Exhibit 1-2, Snow on Cholera. What do you believe was the purpose of each of the following observations by Snow?

“small white, flocculent particles” in the water from the Broad Street pump

the location of cholera deaths as shown in Figure 1-18

people who died avoided the pump on Marlborough Street and instead had the water from the Broad Street pump

“the greatest number of attacks in any one day occurred on the 1st of September . . .”

“On September 8th—the day when the handle of the pump was removed . . .” To what extent do you think removing the pump handle was effective in stopping the disease outbreak?

11) How does quantification support the accomplishment of the four aims of epidemiology?

12) How did Koch’s postulates contribute to the advancement of epidemiology? To what extent is identification of specific agent factors a prerequisite for tracking down the causes of disease outbreaks?

13) What are the characteristics that distinguish pandemic disease from epidemic disease? Name some examples of notorious pandemics that occurred in history. Why did the Spanish Flu of 1918 qualify as a pandemic? In giving your answer, be sure to distinguish among the terms epidemic, pandemic, and endemic.

14) Identify some infectious diseases that could reach pandemic occurrence during the 21st century. What conditions do you believe exist at present that could incite the occurrence of pandemics? Why have public health officials been concerned about the emergence of new diseases such as “bird flu”? Speculate about what might happen to organized society and the healthcare system should an outbreak of pandemic influenza occur.

15) The Black Death that occurred during the Middle Ages eradicated a large proportion of the world population at that time. Estimate how likely it would be for a similar epidemic of plague to develop during the current decade.

16) In developed countries, many safeguards exist for the prevention of foodborne illness. Discuss how it would be possible for a foodborne illness outbreak such as the one caused by E. coli to erupt in a developed country.

18_ On the basis of your own ideas, discuss how epidemiology can help to discover the causes of outbreaks of new epidemic diseases, e.g., Ebola Virus Disease. To what extent is it possible to control epidemic diseases without having precise information about their causal agents? This question also relates to question 12.

19) What is the definition of health disparities? Give some examples from your own observations or examples that you may have read about in the media. Find some examples of research on health disparities in a professional journal such as the American Journal of Public Health or the American Journal of Epidemiology.

20) How would you account for racial and ethnic disparities in age-adjusted mortality from heart disease and stroke in the United States?