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Objectives In this session, all the participants will able to : Define Epidemiology. Define Epidemiologic Transition. Explain the theory of Abdel Omran and its main points Explain the stages of Epidemiologic Transitions. 2

What is epidemiology? Epidemiology, branch of medical SCIENCE that studies the distribution of DISEASE in human populations and the factors determining that distribution, chiefly by the use of STATISTICS. 3

THE EPIDEMIOLOGIC TRANSITION The Epidemiologic transition is that process by which the pattern of mortality and disease is transformed from one of high mortality among infants and children and episodic famine and epidemic affecting all age groups to one of degenerative and man-made diseases (such as those attributed to smoking) affecting principally the elderly. 4

Epidemiologic Transition? Epidemiologic Transition? Back in 1971, Abdel Omran published a seminal paper where he posited his THEORY OF EPIDEMIOLOGIC TRANSITION THEORY OF EPIDEMIOLOGIC TRANSITION THEORY OF EPIDEMIOLOGIC TRANSITION THEORY OF EPIDEMIOLOGIC TRANSITION 5 To characterize population change. The epidemiologic transition is a stage of development characterized by a shift in population growth, life expectancy and disease patterns. The 5 main points are listed below

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Stage I: Pestilence and Famine Infectious and parasite diseases were principle causes of death along with accidents and attacks by animals and other humans. Thomas Malthus called these caused of death “natural checks” Most violent Stage I epidemic was the Black Plague(bubonic plague or black death) probably transferred to humans by fleas from infected rats 7

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Black Plague Originated among Tatars in present day Kyrgyzstan Diffused to present day Ukraine when Tatar army attacked an Italian trading post on the Black Sea Italians fleeing carried the infected rats on ships west to major coastal cities of Southeastern Europe in

continued The plague diffused from the coast to inland towns and then to rural areas It reaches Western Europe in 1348 and Northern Europe in million Europeans died from 1347 to This was one-half of the continents population. In China, 13 million died from the plague in

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Stage II: Receding Pandemics Improved sanitation, nutrition, and medicine during the Industrial Revolution reduced the spread of infectious diseases. Death rates did not improve immediately and universally during the early years of the Industrial Revolution. Poor people who crowded into Industrial Cities had high death rates due to cholera, an acute case of diarrhea and vomiting that can kill within hours if left untreated. 12

Stage III: Degenerative Diseases Associated with the chronic diseases of aging Heart disease and cancer Sub-Saharan Africa and South Asia have low incidences of cancer primarily because of low life expectancy. 13

Degenerative Diseases 14

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Stage IV: Delayed Degenerative Life expectancy of older people is extended through medical advances. Cancer medicines, bypass surgery, better diet, reduced use of tobacco, and alcohol However, consumption of non-nutritious food and sedentary behavior have resulted in an increase in obesity in this stage. 16

Stage IV: Delayed Degenerative 17

Stage IV: Delayed Degenerative 18

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Possible – Stage 5 Infectious Diseases Reemergence of infectious and parasitic diseases; diseases thought to have been eradicated or controlled return, and new ones emerge 20

3 Possible Reasons for Stage 5 Evolution – new strains due to drug resistance (malaria) Poverty- more infections due to unsanitary conditions, expensive (TB/ “consumption”) Increased connections – spread through relocation diffusion (H1N1/swine, severe acute respiratory syndrome (SARS) – entered U.S. through NY, CA, and FL. 21