Chapter 1: Epidemiology and Its Progress

Epidemiology and Its Changing Definitions Most acceptable definition: “The study of the distribution and determinants of health related status or events in specified populations.“ (Last, 1988) 19th century: Infection causes disease. Today: Infection, nutrition, environment, and trauma cause disease.

Role of Advanced Practice Nursing in Public Health (1 of 3) Lillian Wald coined term “public health nursing” in 1893. Main idea was prevention of disease. Public health nursing promotes, protects, and restores health of populations and prevents disease and disability.

Role of Advanced Practice Nursing in Public Health (2 of 3) Florence Nightingale helped create “district nurses.” They promoted health and prevented diseases through nursing care and education. Figure 1-1 Florence Nightingale. Source: National Library of Medicine; URL: http://ihm.nlm.nih.gov/luna/servlet/view/search?q= B020487; Accessed April 5, 2010.

Role of Advanced Practice Nursing in Public Health (3 of 3) Advanced practice nurses take a leading role in: Public health administrative activities Responding to public health emergencies Community education, vaccination, and screening Community assessment

Historical Epidemiological Studies (1 of 2) Vaccination was introduced by Edward Jenner in 1798. John Snow studied cholera transmission. Pioneer in modern epidemiology Sir Richard Doll studied effects of asbestos exposure. Smith and Spaulding (1959) traced a paralysis outbreak in Morocco to contaminated olive oil used by lower socioeconomic communities.

Historical Epidemiological Studies (2 of 2) Goldberger, Waring, and Tanner (1914) conducted classic study of pellagra transmission. Clarke and Anderson (1979) investigated effectiveness of Pap smear screening in prevention of cervical cancer. Legionnaire’s disease was identified in 1976 by epidemiological investigation. Epidemiological control efforts on a mass scale contributed to the eradication of smallpox in 1980.

Disease Transmission Dynamics (1 of 4) Diseases are classified as communicable or noncommunicable. Communicable diseases are transmitted from: Human to animal Animal to animal Animal to human Social and environmental factors affect transmission dynamics.

Disease Transmission Dynamics (2 of 4)

Disease Transmission Dynamics (3 of 4) John Graunt is considered the first epidemiologist. In 17th century described relationship between population and disease. Also accurately estimated the population of London. Using Graunt’s data, William Farr and Rowe Edmonds developed idea of vital statistics.

Disease Transmission Dynamics (4 of 4) Importance of health statistics has been demonstrated in recent years by such projects as: Framingham heart study Community intervention trials of fluoride supplementation in water Surgeon General’s report on smoking and health

Public Health Surveillance (1 of 2) “Ongoing, systematic collection, analysis, and interpretation of data that is then disseminated to those responsible for preventing diseases and other health conditions.” (CDC)

Public Health Surveillance (2 of 2) Agent, host, and environment (“epidemiological triangle”) are most important in disease transmission. Epidemic—outbreak limited in space and time. Pandemic—epidemic extending to whole country or large part of the world. A disease is said to be endemic if present in an area for a long period of time.

Prevention (1 of 2) Quarantine and isolation are used to contain a disease. Epidemiological research helps understand concepts of epidemiology. Can be done with or without human participants. Outbreak investigation focuses on a particular disease. Often leads to discovery of new microorganisms.

Prevention (2 of 2) Primary prevention Secondary prevention Actions that prevent disease or disability in an individual. Secondary prevention Actions that lead to early identification, diagnosis, and treatment of disease. Tertiary prevention Actions that promote activities of daily living to limit progression and complications of disease.