What is epidemiology?

Epidemiology is considered to be the backbone of public health; with many suggesting that public health itself is merely applied epidemiology[1].  Epidemiology, when paired with biostatistics, contributes much of the science behind public health. It also has important implications for clinical medicine. Leon Gordis defines epidemiology as “the study of how disease is distributed in populations and the factors that influence or determine this distribution[2].”  Understanding disease distribution is key to managing diseases and stopping their spread.

An additional question to consider is: Why is epidemiology important? There are several reasons, actually. The practices of public health and medicine depend upon epidemiology, and much of everyday life revolves around it. Gordis notes that epidemiology is significant because it:

• Identifies the cause of a disease or disease risk factors
• Determines extent of disease or disease burden
• Studies the natural history and prognosis of a disease
• Evaluates both existing and new developed preventive therapeutic measures and modes of health care delivery
• Provides the foundation for developing public policy relating to environmental problems, genetic issues, and other considerations regarding disease prevention and health promotion
• Determines if there is an association between a disease and an exposure2

You likely hear about epidemiology every day, perhaps without knowing. In short, epidemiology is what keeps you from getting sick, and if you do get sick, it aims to know who, what, when, where, why, and how.  Through the news media, epidemiology alerts you to risk factors and attempts to educate on ways to protect yourself. Epidemiology may not be a word you commonly hear, but the practice and teaching of epidemiology is all around you. Once you begin to notice epidemiology, it is hard NOT to notice it.  I certainly find myself unable to open the newspaper or turn on the television without being grabbed by an epidemiological anecdote. In just a short time you will see that epidemiology is….

Delicious

Source: Inquistr.com

I don’t know about you, but I tend to think that clean, bacteria-free food is much tastier than the alternative.  Epidemiology helps keep our food supply safe. When a foodborne illness is suspected or the food supply is compromised, epidemiologists come to the rescue. They determine the source of contamination, and if applicable, ensure that the contaminated source is cut off from consumers. Unfortunately, epidemiologists have been in overdrive as of late, and we are all too familiar with food recalls. You may remember the largest egg recall in U.S. history, occurring in 2010. The recall was prompted by an epidemiological data showing that eggs infected with the salmonella bacteria caused illness in more than 1,500 people[3]. It is possible that you yourself have been involved in the investigation of a food borne illness. If you have ever reported a suspected or known case of such illness to your local health department, you know how miserable such an event can be. I am thankful there are people out there trying to ensure food outbreaks do not occur and that their impact is limited.

Sexy

Source: blog.therealestatehomeguide.com

Well, sometimes, at least. An outbreak of respiratory illness recently brought epidemiologists to the Playboy Mansion for investigation. While you might suspect Hugh Hefner’s pad to be a breeding ground for a certain kind of disease, the illness in question here is a form of Legionnaire’s disease. Legionnaire’s is a fairly common infection, with the CDC estimating that between 8,00 and 18,000 people are hospitalized in the U.S. with the condition each year. [4] The bacteria that causes Legionnaire’s, known as Legionella, thrives in warm water. For this reason, the suspected sources of contamination at the Hefner Home include suspects include both a hot tub and a fog machine. Epidemiologists on this scene of this investigation will be responsible for determining the actual exposure of all persons infected with the disease, along with testing the suspected sources for bacteria. It’s a tough job, but somebody has to keep Hef and all his ladies safe from harm.

To read more about the investigation at the Playboy Mansion, click here:

http://www.chicagotribune.com/news/ktla-playboy-mansion-outbreak,0,961582.story?track=rss

Controversial

Source: Medicexchange.com

When an epidemiological study reveals new groundbreaking information, the information isn’t necessarily met with open arms. While new data is exciting, it isn’t always well received or taken as the definitive word on a subject. Take for example, the new mammography guidelines issued in 2009 by the U.S. Preventive Services Task Force. This information developed by the taskforce was intended to make decisions regarding mammograms easier. Instead, the report unleashed a myriad of opinions on the subject, including the American Cancer Society, who disagreed with the findings. Epidemiologic research is intended to aid the public and medical professionals alike, but unfortunate circumstances exists where the data merely complicates the situation.  In this situation, we see well-intentioned organizations and professionals pitted against each other, claiming that the evidence on which they rely is the most, well, reliable. And so, research will continue, as each study builds upon the last, until an undeniable conclusion can be reached. Until then, controversy remains.

Epidemiology is all around you, and you may have even contributed to the study of epidemiology. It is constantly in action, and constantly spurring action.  It is an ongoing adventure.

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[1] Turncock, Bernard. (2007). Essentials of Public Health. Sudbury, Massachusetts: Jones and Bartlett Publishers.

[2] Gordis, Leon. (2009). Epidemiology (4th ed.). Philadelphia, PA: Saunders Elsevier.

[3] NY Times. (2010, Sept 23). Egg contamination and recalls. The New York Times. Retrieved from: http://topics.nytimes.com/top/reference/timestopics/subjects/e/eggs/contamination_and_recalls/index.html

[4] Centers for Disease Control and Prevention, National Center for Immunization and Respiratory Diseases (2008). Patient facts: learn more about legionnaires’ disease.  Retrieved from: http://www.cdc.gov/legionella/patient_facts.htm