Public Health Introduction

1. Public Health

2. What is ‘Health’ ?
 Oxford dictionary
State of being well in body or
mind

3.  “Health is a state of complete physical, mental and
social well-being and not merely the absence of
disease or Infirmity.”
W.H.O. Definition of Health

4. DETERMINANTS OF HEALTH
 The factors which influence health lie both within
the individual and externally in the society .
 These factors which promoting or deleterious of
health.

5. Determinants of Health
1. Biological determinant
2. Behavioural & socio-cultural conditions
3. Environment
4. Socio-economic conditions
5. Health services
6. Aging & population
7. Gender
8. Other factors.

6. 1) Biological determinants
A number of diseases are known to be of
genetic origin, e.g.
 Chromosomal anomalies
 Mental retardation
 Diabetes

7. 2)Behavioral and social culture conditions
 Life style is “ The way people live”
reflecting a whole range of social values ,
attitude and activities.
 It is composed of cultural and behavioral
patterns and lifelong personal habits that have
developed through processes of socialization .

8. 2)Behavioral and social culture
conditions
Life style in developed c.
 Smoking
 Obesity
 Drug addiction
Life style in developing c.
 Poor nutrition
 Personal hygiene

9. 3) Environment
 Environment is classified as “internal”
and “external”.
 Internal : each & every component part, every
tissue, organ & organ system & their harmonious
functioning within the system
 External: all that which is external to the
individual human host.
 It can be divided into physical, biological and
psychosocial components.e.g
eating habits, life style &
personal habits

10. 4) Socio-economic conditions
 It influence human health
1. Economic status
2. Education
3. Occupation
4. Political influence

11. 4) Socio-economic conditions
 Economic status
 When ↑
 ↓ morbidity
 ↑ life expectancy
 Improving the quality of life
 Improving the purchasing power
 ↑ heart diseases, diabetes & obesity.
 Family size.

12. 4) Socio-economic conditions
 Education
1. ↑ literacy ( male) ---------↓ poverty
2. ↑ literacy ( females)------- ↓ malnutrion , ↓ infant
mortality rate

13. 4) Socio-economic conditions
 Occupation
1. State of being employed in productive work
promotes health
2. Loss of work mean loss of income & cause
psychological & social damage.

14. 4) Socio-economic conditions
 Political system
1. Resource allocation.
2. Health services available.
3. Manpower policy.

15. 5) Health services
 Improve health status of population
by:
1. Immunization of children
2. Provision of safe water supply can
prevent mortality & morbidity from
water borne diseases.
3. Care of pregnant women reduce of
maternal & child morbidity &
mortality.

16. 6) Ageing of the population
• ↑ prevalence of chronic diseases & disability

17. 7 ) Gender
 Nutrition
 Reproductive health
 Ageing
 Life style
 Increase awareness among
policy makers of women’s
health issues & encourages
their inclusion in all
development plans as a
priority

18. 8) Other factors
 Food & agriculture
 Industry
 Social welfare

19. Concept of Disease

20. Disease
 Oxford English Dictionary – the condition of
body or some part of organ of body in which its
functions are disrupted or deranged.
 Simplest definition – ‘Opposite to Health’.
 Disease is a physiological/psychological
dysfunction.

23. The Triangle of Epidemiology

24. Agent Factors
What are the “Types of
agent factors” ???

25. Host Factors
1. Demographic characteristic ( age, sex, ethnicity)
2. Biological characteristic ( genetic factors,
cholesterol in the blood)
3. Social & economic characteristic ( socio-
economic status, education, occupation, stress,
housing)
4. Lifestyle factors (living habits, nutrition,
smoking, physical exercise )

26. Environmental factors
 Intrinsic
 Extrinsic
1. Physical environment
2. Biological environment
3. Psychosocial environment

29. Natural history of
disease

30. Natural History of Disease
 It is the progression of a disease process in an
individual over time, in the absence of
treatment.
 The time frame of disease may vary from
individual to individual.

31. Stage of susceptibility
 The process begins with the appropriate exposure to the
factors.
 For an infectious disease, the exposure is a
microorganism.
 For cancer, the exposure may be tobacco smoke (for
lung cancer)

32. Stage of subclinical disease
 pathological changes occur without the individual
being aware of them.
 extending from the time of exposure to onset of
disease symptoms,
 called the incubation period (infectious diseases)
& the latency period (chronic diseases).
 Disease is asymptomatic (no symptoms)
 Incubation periods of varying from minutes to
decades .

33. Exposure Clinical Effect Incubation/Latency
Period
Salmonella Diarrhea, often with
fever and cramps
6–48 hr
Hepatitis A virus Hepatitis 14–50 days, average 4
weeks
Hepatitis B virus Hepatitis 50–180 days, usually 2–3
m
Human immunodeficiency
virus
AIDS <1 to 15+ years

34.  Although disease is not apparent during I.P,
pathologic changes may be detectable with
laboratory, radiographic, or other screening
methods.
 intervention at this early stage is more
effective than treatment given after the
disease has progressed and become
symptomatic

35. Stage of clinical disease.
 The onset of symptoms marks the transition from
subclinical to clinical disease.
 Most diagnoses are made during the stage of
clinical disease.
 The disease process ends either in recovery,
disability or death