Download Epidemiology

Endemic - Epidemic - Pandemic
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Endemic
Transmission occur, but the number
of cases remains constant
Epidemic
The number of cases increases
Pandemic
When epidemics occur at several
continents – global epidemic
Number of Cases of a Disease
Endemic vs Epidemic
Endemic
Time
Epidemic
Epidemiology :
Definition :( study of disease
occurrence and distribution in the
community) .
In other word Epidemiology means
The study of distribution and
determinants of health related states or
events in specialized population and the
application of the study to control of
heath problems .
Uses of epidemiology :
Identify the aetiology or the cause of the
disease and the risk factor that increases
a person's `risk for a disease.
To determine the extent of a disease
found in the community. What is the
burden of a disease in the community
,this is critical for planning health series.
 Study the natural history and prognosis of
the disease.
 To evaluate new preventive and
therapeutic measures and new modes of
health care delivering.
 To provide the foundation for the
developing public policy and regulating
decisions related to environmental
problems
Chronic or Non Communicable Diseases
(NCDs)
Chronic diseases are the major cause of deaths
worldwide .
Increase rate of NCDs in low and
intermediate income countries .
Interventions are effective and can reduce
burden of disease .
Some of NCDs have infectious etiology,
helicobacter pylori bacteria is the causative
agent for stomach cancer .
The 10 leading causes of death
in the world, 2000 and 2012
Ischemic heart disease, stroke,
lower respiratory infections and
chronic obstructive lung disease
have remained the top major
killers during the past decade.
Top 15 CAUSES of death in USA
1. Heart Disease
2. Cancer
3. Lung Disease
4. Accidents
5. Stroke
6. Alzheimer's
7. Diabetes
8. Influenza-Pneumonia
9. Nephritis/Kidney
10. Suicide
11. Blood Poisoning
12. Liver Disease
13. Hypertension/Renal
14. Parkinson
15. Homicide
Causes of death in developing countries Causes of death in developed countries
HIV-AIDS
Ischaemic heart disease
Lower respiratory infections
Cerebrovascular disease
Ischaemic heart disease
Chronic obstructive pulmonary disease
Diarrhea
Lower respiratory infections
Cerebrovascular disease
Childhood diseases
Malaria
Tuberculosis
Lung cancer
Car crash
Stomach cancer
Hypertensive heart disease
Chronic obstructive pulmonary disease
Tuberculosis
Measles
Suicide
Developed vs. developing economies]
Top causes of death, according to the World Health Organization report for the
calendar year 2001:
Epidemiology
of Chronic Non Communicable Diseases (NCDs)
Chronic disease :
All impairments or deviations from normal which
have one or more of the following characteristics:
1. Permanent .
2. Leave residual disability .
3. Caused by a non-reversible pathology .
4. Required special training of the patient for
rehabilitation .
5. Required long period of supervision,
observation or care .
Problems in etiological investigations of
NCDs
1. Absence of a known agent .
2. Multifactor's nature of etiology .
3. Long latent period .
4. Indefinite onset .
5. Differential effect of factors on
incidence and course of the disease .
Prevention of NCDs received little
attention by policy makers, medical
professionals, and general public
because
1. The extent is less sufficiently examined.
2. Long delay between cause and effect .
Primary prevention is possible for most NCDs
Due to the following facts :
1. Large population differences in incidence
and mortality of NCDs .
2. Dynamic national trends in incidence and
mortality rates of most NCDs .
3. Rapid changes in risk of many NCDs
among migrants population .
4. Positive results of intervention trials .
5. Identification of modifiable risk factors of
many NCDs .
Causes of shift of epidemiological
studies toward the NCDs rather than
acute
infectious
and
nutritional
deficiency diseases
1. Demographic changes :
 Decrease in infant mortality rate .
 Decrease in infertility rate .
both leads to population aging .
2. Urbanization and socioeconomic ransformation
A.
B.
C.
D.
E.
F.
Changes in community relationships .
Changes in life style .
Decreases concerns about moral believes .
Human mobility .
Expansion of education .
Participation of women in labor force .
3. Changes in nutritional pattern
A.
B.
Rapid increase in food energy availability and
consumption .
Obesity is emerging as a major public health
problem .
4. Other causes :
A. Smoking epidemic .
B. Increase in alcohol consumption .
C. Sedentary life style .
Preventive health
care Level
Definition
Primary
prevention
Methods to avoid occurrence of disease either
through eliminating disease agents or increasing
resistance to disease. Examples
include immunization against disease,
maintaining a healthy diet and exercise regimen,
and avoiding smoking.
Secondary
prevention
Methods to detect and address an existing
disease prior to the appearance of
symptoms. Examples include treatment
of hypertension (a risk factor for many
cardiovascular diseases), cancer screenings
Tertiary
prevention
Methods to reduce negative impact of
symptomatic disease, such as disability or death,
through rehabilitation and treatment. Examples
include surgical procedures that halt the spread
or progression of disease