1. Epidemiological Transitions
Population VII
Epidemiological Transitions

3. Epidemiological Transition Model
ETM-within the past 200 years, virtually every country has experienced an epidemiological transition-a long-term shift in health and disease patterns. This transition from a high level of death for young people (communicable/infectious diseases) to low levels of death with death concentrated among the elderly (degenerative diseases). Therefore, the variation by age of mortality is reduced. People survive to advanced ages and then die quickly once reaching that advanced age. This transition, according to Abdel Omran (‘71), is the result of a country undergoing the process of modernization or economic development.
The ETM closely parallels the DTM.
***In the past, parents buried their children; now, children bury their parents. (more developed countries). This process leads to a rectangularization of death.
Stage 1
Epidemics/Pandemics: Infectious and parasitic diseases, famine
Ex: Black Plague (25 million Europeans died)
The transition from stage 1 to stage 2 (from hunting and gathering to primary food production), allows for an increase in infectious and parasitic diseases to occur due to an increase in human contact and contact with possible vectors.
Stage 2
Receding epidemics, infectious diseases (affects high proportion of population, but in isolation)
Ex: Cholera (contaminated water supply), Latin America-leptospirosis (Weil’s Disease), Tuberculosis (see map), West Africa-Ebola (3,000 confirmed cases), Sub-Saharan Africa-Malaria, AIDS, Meningitis

4. Epidemiological Transition Model
The transition from infectious to chronic, degenerative diseases now occurs
Stage (What does a doctor really cure?)
Degenerative and human-created disease
Ex: Cardiovascular disease and Cancer
Stage 4
Delayed degenerative diseases
Ex: Alzheimer's, Diabetes
Stage 5?
Re-emerging infectious and
parasitic disease
Ex: Malaria, TB, AIDS
What is causing Stage 5? Where is it located?
What about MERS (South Korea)? Bird Flu-U.S.?

5. WHAT IMPACTS THE ABILITY OF DISEASES TO DIFFUSE?
Population density and urbanization – High density equates to high rate of diffusion. Over 50% of the global population lives in urban areas. With more people living in dense conditions, there is more frequent contact between more individuals, allowing disease transmission to easily occur. (Contagious Diffusion)
Migration and global travel –. (Relocation Diffusion)
Environmental degradation –especially common in vector borne diseases (Zika Virus)
All of the above factors will influence the rate of diffusion OR …
***R0-R Nought-average number of people who will contract the disease from one contagious person. This rate of transmission does not include vaccinated people. Any R Nought number greater than one could potentially lead to an epidemic.
Example: 1918 Swine Flu (R Nought of 2.6-killed 50 million people “Pandemic”)

6. Regionalizing Diseases
Sub-Saharan Africa-
South America-
South Asia-
East Asia
Russia and Surrounding States-

7. The World’s Deadliest Infectious Diseases

8. AIDS/HIV+ 2010 world distribution: 23 million in Sub-Saharan Africa
5+ million in Asia (India, China, SE Asia)
2 million in Latin America (Caribbean-Haiti)
Sub-Saharan Africa
70% of HIV cases
Zimbabwe, Botswana, Zambia, South Africa, Kenya
Increased death rates
Declining life expectancy

9. New Disease: The Zika Virus
symptoms of
Zika virus- fever, rash, joint pain, or conjunctivitis (red eyes). Symptoms typically begin 2 to 7 days after being bitten by an infected mosquito. Pregnant mothers can transmit virus to baby and baby could possibly be born with extremely undersized head.

10. Rectangularization of Death
Mortality rates declining, more people surviving to an advanced age due access to medicine and medical care.