Public Health- Ep transition pt1.pdf

Faculty of Medicine Public Health (BMS 214) ‫الصحة العامة‬ Lecture 14+15 Epidemiological Transition Global Health Risks By Tariq N. Al-Shatanawi MPH PhD 25+26-8-2024 1 2  TRANSITION  HEALTH...

Faculty of Medicine Public Health (BMS 214) ‫الصحة العامة‬ Lecture 14+15 Epidemiological Transition Global Health Risks By Tariq N. Al-Shatanawi MPH PhD 25+26-8-2024 1 2  TRANSITION  HEALTH TRANSITION - changes in health status and economic, sociodemographic, and environmental health determinants.  DEMOGRAPHIC TRANSITION - changes in population size and distribution: birth and death rates and population pyramids.  EPIDEMIOLOGICAL TRANSITION - move from a disease pattern dominated by infectious diseases to one characterized by noncommunicable diseases (cancers, cardiovascular and injury). 3  TRANSITION  HEALTH RISK TRANSITION - changes in size and nature of population strata exposed to risk behavior and risk exposures. TECHNOLOGICAL TRANSITION – rapid advances in science, biotechnology, information technology and health sciences. 4  Epidemiological Transition  Changing patterns in death and illness due to modernization are changed- from generally infectious, parasitic and nutritional diseases to western diseases chronic degenerative diseases. 5  Epidemiological Transition  Most changes in epidemiological transition occur through substantial changes in living standards, and ways of life.  This includes:  Access to medical care,  Preventative medicine and  Public health but also other factors such as:  Adaptation to the Western lifestyle includes stress, eating patterns, urbanized living etc.. 6  2000 ====  Age of declining cardiovascular mortality, aging, lifestyle modifications, emergent and resurgent diseases.  Increases in life expectancy (which approach 80 to 85 years or longer, especially for females), with increased chronic diseases and aging.  Changes in lifestyle, cessation of smoking, low-fat diets, and regular and aerobic exercise, better nutrition and malnutrition). 7  Emergence of new diseases and resurgence of old diseases The WHO in 1998 listed some 30 such diseases recognized since 1970, Viral diseases are those caused by HIV, Hepatitis B and C, Ebola, Hanta pulmonary and renal syndromes, Monkeypox, Rift Valley fever and several hemorrhagic fevers. 8  The Health Transition  Health transition: the shifts that have taken place in the patterns and causes of death in many countries.  Previously, the health transition has been covered by two separate terms: 1. Demographic transition 2. Epidemiological transition 9  The Health Transition …  The health transition is a more appropriate term, as it covers the full range of social, economic and ecological changes driving the epidemiological and demographic transition. 10  The Demographic Transition Theory  Demographic transition - describing the change from high fertility and mortality rates in less developed societies to low fertility and low mortality rates in 'modem' societies  The transition from a combination of high birth rate and high death rate to a combination of low birth rate and low death rate, with the decline in birth rate lagging behind the decline in death rate so that during the middle phase of the transition there is population explosion. 11  The Epidemiologic Transition  Epidemiological transition - which was introduced to describe the changes in mortality and morbidity patterns (from infectious to chronic diseases) as societies' demographic, economic and social structures changes  It comprises three stages characterized by categories in which fertility levels and causes of death are grouped 1. The age of pestilence ‫ الوباء‬and famine ‫المجاعة‬ 2. The age of receding pandemics 3. The age of chronic diseases Epidemiologic transition comprises the first three stages of the health transition. 12  1-The age of pestilence and famine  This first stage of the health transition stage (the age of pestilence and famine) is characterized by mortality that has prevailed throughout most of human history.  Epidemics, famines, and wars cause huge numbers of deaths.  The lack of sufficient infrastructure for most services high levels of mortality and fertility.  Infectious diseases are dominant, causing high mortality rates, especially among children.  Life expectancy between 20-40years  Some developing countries are still in this stage. 13  2-The age of receding pandemics  This stage began in the mid-19th century in many of what are now developed countries.  It involved a reduction in the prevalence of infectious diseases and a fall in mortality rates.  Consequently, life expectancy at birth climbed rapidly from about 35 to 50.  Increased economic growth leads to a sharp fall in deaths from infectious diseases, and malnutrition.  Finally, the introduction of modern healthcare and health technologies, e.g., immunization programs and antibiotics, enable the control and elimination of groups of infectious diseases such as acute bronchitis, influenza, and syphilis. 14  3-The age of chronic diseases  In the third stage the elimination of infectious diseases makes way for chronic diseases among the elderly.  While improved healthcare means that these are less lethal than infectious diseases, they nonetheless cause relatively high levels of morbidity.  Increasingly, health patterns depend on social and cultural behavior, such as patterns of food consumption and drinking behavior.  Due to low levels of mortality and fertility, there is little population growth.  When the health transition is at an advanced stage, life expectancy may exceed 80 years. 15  The age of chronic diseases …  This stage occurs at different rates in different nations: in both developed and developing countries, mortality rates are driven by socially determined factors; in developed nations, they are also driven by medical technology.  It becomes necessary to ensure sufficient social and health-care investment for all age groups.  At the same time, there is increased demand for healthcare related to the diseases of older people. 16  The Epidemiologic Transition………  The epidemiologic transition (MADE UP OF STAGES 1-3) has not been all blessing certain changes associated with the transition have given rise to many problems which include: 1. The nuclearization of the family 2. The destruction of group cohesion 3. Rise in mental illness 4. Crime, delinquency ‫االنحراف‬ 5. Drug dependency boosts the demand/for psychiatric help 6. Alarming rise in medical costs 17  The next stage in the health transition: what lies ahead?  To explore possible future global health transitions Martens (2002) developed a set of possible scenarios that paint pictures of possible futures and explore the various outcomes that might result if certain basic assumptions are changed.  These scenarios can be used to explore the global and regional dynamics that may result from changes at a political, economic, demographic, technological and social level. 18  The Scenarios  Four clusters of scenarios were developed and are defined along two main dimensions:  Group A  The first dimension relates to the extent both of economic convergence and of social and cultural interactions across regions.  Group B  the second has to do with the balance between economic objectives and environmental and equity objectives. 19  Future stages of the health transition  Based on these scenarios Martens (2002) described the developments in the health status of populations according to three potential future 'ages‘4-6: 1. The age of pestilence ‫ الوباء‬and famine ‫المجاعة‬ 2. The age of receding pandemics 3. The age of chronic diseases 4. The age of emerging infectious diseases 5. The age of medical technology 6. The age of sustained health 20  4- The age of emerging infectious diseases  In this stage, the emergence of new infectious diseases or the re- emergence of 'old' ones will have a significant impact on health.  Several factors will influence this development:  Travel and trade  Microbiological resistance  Human behavior  Breakdowns in health systems  Increased pressure on the environment  The overuse of antibiotics and insecticides, combined with inadequate or deteriorating public health infrastructures will hamper or delay responses to increasing disease threats. 21  5- The age of medical technology  To a large extent, increased health risks caused by changes in life-style and environmental changes will be offset by increased economic growth and technology improvements in the age of medical technology.  If there is no long-term, sustainable economic development, increased environmental pressure and social imbalance may propel poor societies into the age of emerging infectious diseases.  On the other hand, if environmental and social resources are balanced with economic growth, sustained health may be achieved. 22  6-The age of sustained health  In the age of sustained health, investments in social services will lead to a sharp reduction in life-style related diseases, and most environmentally related infectious diseases are will be eradicated.  Health policies will be designed to improve the health status of a population in such a way that the health of future generations is not compromised. 23  Health Transition – Developed Countries  Currently, most developed countries are in the third stage of the health transition:  fertility rates are low.  causes of diseases and deaths have shifted from infectious to chronic diseases. 24  Health Transition – Developing Countries  The health situation in developing countries varies greatly from one country to another.  In most, there is still very low life expectancy; this is due largely to malnutrition and the lack of safe drinking water, which are compounded by poor healthcare facilities.  In other countries, however, particularly in Asia and Latin America, chronic diseases have now become more important than infectious diseases. 25  Health Transition – Developing Countries …  The same large variation is reflected in the demographic situation.  In countries such as China and Thailand fertility rates are very low; in others they are very high.  Due to sub-national differences of an economic, social or ecological nature, there may also be large differences within a single country. 26  Health Transition – Developing Countries …  It is widely believed that, with increasing economic growth, developing countries will follow the same pattern of health transition as Europe and North America. Many countries, especially the poorest, will not 'trade' infectious diseases for chronic diseases; instead, they may even suffer a 'double burden' of disease. 27  Health Transition …  Future developments will not be the same for all countries, and developing countries are unlikely to follow the same transition path as the developed world. 28