Epidemiology Foundation Standard 3 Teacher Notes: The purpose of the PowerPoint is to introduce students to the field of epidemiology. Time for lesson: 25 minutes, including class discussion time. The objectives are to: Explain epidemiology. Understand terminology associated with the investigation of disease outbreaks: surveillance, monitoring, prevalence, morbidity, mortality and risk. As students progress through their health science education, the understanding of basic terminology will help them make sense of what they read in the future. The terms in this unit will appear again and again as students read articles and study health science concepts. Foundation Standard 3 3.14 Explain the impact of emerging issues such as technology, epidemiology, bioethics, and socioeconomics on healthcare delivery systems.

Epidemiology is the study of health and disease in human populations. What is epidemiology? Epidemiology is the study of health and disease in human populations. It’s all about public health. Teacher Notes: This slide is designed to create a common definition for epidemiology, and to help students understand that epidemiologists study more than just communicable diseases, but also a number of conditions that affect the public health. Photo courtesy of CDC/ Dr. David M. Morens, Dr. Steve Thacker, from the Public Health Image Library.

Epidemiologists Epidemiologists study Literally – they “count”! Communicable disease Cardiovascular disease Cancer Mental illness Accidents And more…. Literally – they “count”!

Epidemiologists Count For example, they count the number of times a condition (disease) occurs in relation to the total number of people. We call that PREVALENCE So, if we counted the number of children with asthma in a community and determined that 5% had asthma, we could say that the PREVALENCE of asthma is 5% in this specific community. Teacher Notes: The purpose of this slide is to further describe what an epidemiologist does, and to help students understand the concept of PREVALENCE. We have included an example. Ask students to give you another example or two of PREVALENCE.

Disease Detectives Epidemiologists investigate disease outbreaks. They determine where an outbreak came from, and how to prevent it. Think if them as “disease detectives.” What if…a number of students at your school become sick with a strange illness. What questions would you ask if you wanted to “investigate” the disease outbreak? Teacher Notes: This slide is asking students to suggest things that a “disease detective” might to when investigating a disease. Student responses may include: Identifying and keeping track of who gets sick. Investigate the activities of the infected persons before they got sick. What do they have in common? Where did they go? What did they eat? The purpose is to find the cause of the illness and determine how to prevent it.

Surveillance Police watch a suspect or location to determine what is taking place. Epidemiologists also practice SURVEILLANCE, but they are searching for and documenting disease. SURVEILLANCE keeps track of a number of public health concerns, including abuse, violence, sexually transmitted diseases, and communicable disease outbreaks. Teacher Notes: This slide explains the concept of surveillance. The key is for students to understand that epidemiologists don’t ONLY respond to outbreaks, they also go out looking for problems. In other words, they are not just reactive – they are proactive. (You may want to spend a few minutes helping students understand the difference. Most people would say that being proactive is a good characteristic for a healthcare professional.)

Monitoring MONITORING uses surveillance data to determine changes in the number of affected (or infected) people. MONITORING tells us if there is more or less of a particular disease/condition. These measurements are used to create a picture of how a disease is affecting society. Teacher Notes: The textbook definition of MONITORING is – The regular review of disease data to determine changes in disease levels. It may be helpful to ask students to suggest examples of surveillance and monitoring. Their ability to generate examples will help them understand and remember the terminology. Photo courtesy of CDC/ Edward Baker, M.D., M.P.H. from the Public Health Image Library.

Incidence INCIDENCE is the number of new cases of a disease or event in a specific population. Photo courtesy of CDC/ Barbara Rice, from the Public Health Image Library. For example, epidemiologists might measure the incidence of influenza in children. Is there anything you could measure the INCIDENCE of in your school?

Morbidity The number of cases of a specific disease in a specific period of time per unit of population, usually described as a number per 1000. During an influenza epidemic, influenza MORBIDITY may reach 300/1000 in children. Teacher Notes: Morbidity is the number of cases of illness, consequently, the 2nd bullet means that 300 out of 1000 children may get the flu during an epidemic, which is about 30%. Photo courtesy of CDC/ Dr. John Noble, Jr, from the Public Health Image Library.

Infant Mortality Rates 2007 Angola 184.4 Austria 4.5 Nigeria 95.5 Spain 4.3 Sweden 2.8 Switzerland Syria 27.7 United Kingdom 5.0 United States 6.4 Venezuela 20.9 Zimbabwe 51.1 A measure of the number of deaths in a given population. The Infant Mortality rate in America is 6.4 deaths per 1,000 live births. Is the data in this chart important? Why? Photo courtesy of CDC, from the Public Health Image Library.

Risk RISK is the likelihood that someone will become infected or develop a condition. RELATIVE RISK may change relevant to a specific factor. A study reports that smokers face a relative risk of dying from lung cancer 24 times higher than non-smokers. Photo courtesy of CDC, Perry, from the Public Health Image Library.

In Review, What Is ?? Epidemiology Prevalence Surveillance Monitoring Incidence Morbidity Mortality Risk Relative Risk Teacher notes: This gives you a chance to review key terms with students.

Epidemic epi-above/upon, demic – people New cases of certain disease/condition that exceeds what is expected Disease, drug abuse, obesity

Pandemic pan-all, demic – people Epidemic of infectious disease that spreads thru large region Smallpox, TB, HIV, H1N1

Now You’re Talking Epidemiology! What is the impact of epidemiology on the healthcare delivery system? Group discussion – Students should divided into groups of 3 – 5 to discuss what they think is the impact of epidemiology on healthcare delivery systems. There are no necessarily right or wrong answers, but students should be able to come up with a number of reasonable examples. Photo courtesy of CDC/ Hsi Liu, Ph.D., MBA, James Gathany, from the Public Health Image Library.