Health is a state of complete
physical, mental and social well being and
not merely the absence of disease or
SPECTRUM OF HEALTH
Negative or marginal health
In apparent disease
This conforms to the WHO definition of
Perfect continuing adjustment between
the individual and the environment.
This definition indicates that health is a
positive dynamic interaction between the
individual and his surroundings with
proper acclimatization to maintain health.
Negative or marginal
If the individual is in a state of
equilibrium, he looks healthy, but he has
no ability to adjust himself to his
surroundings, then he is going to fall ill on
the slightest adverse stimulus.
Disease is a state of departure from
normal to the extent that the ordinary
physiologic processes of the tissues and
organs are not enough to restore the body
to its normal functions. Unapparent
disease (also called pre-clinical) is not
recognized by the individual, but can be
discovered by examination and screening
The individual is aware that s/he is
suffering from an illness, whether s/he
seeks medical care or not.
Epidemiology (Epi = on,
and demos = people)
Epidemiology is the subject concerned
with study of what happens to people
when involved by disease, whether
communicable or non-communicable
It is defined as the study of distribution,
frequency, determinants, and dynamics of
diseases in human populations.
Factors affecting the
occurrence of a disease
Human being (host factors)
Heredity and genetic factors
Age and sex
Previous immunologic experience
Life style: e.g. smoking.
The physical environment
The Biologic environment
The social/cultural environment
Chemical agents: Examples are
poisons, insecticides, and even some drugs.
Physical agents: Excessive heat or cold
, electricity, irradiation, ....
Mechanical agents: causing injuries or
e.g., phenylketonuria, galactosemia,..
Genetic agents: as in Down's syndrome.
Functional: Dysfunction of certain organs or
gland may produce disease, e.g., Diabetes
These are factors that make an
individual, a family, a group of
individuals, or a community, more prone
to a specific disease due to the presence
of a certain factor which is not the direct
The causative agent may be known or
The risk factors are related to the host or
his/her self specific environment.
Public health is "the art and science of
promoting health, preventing disease and
increasing the span of healthy life through
organized efforts of the society".
Another definition, which has almost the
same meaning "public health can be
defined as the combination of sciences,
skills and beliefs that are directed to the
maintenance and improvement of the
health of all the people."
Essential public health
Protection of the environment
Health legislation, and health regulations
Prevention and control of communicable
Care for special groups as mothers,
children, and workers in certain hazardous
Assessment of health needs, plans and
supports the provision of health care
services to the population
Community Health /
Is the application of the principles of
public health to communities.
A community is a group of individuals
sharing an identity, culture, and operates
through common institutions and
organizations. A health Center in a rural
or an urban area is responsible for the
health of the community they serve within
their catchment area.
is the science and art of application of the
different levels of prevention at the
population, community, and individual
PATTERNS OF CARE
Levels of Prevention:
Early detection of diseases
Prompt and appropriate treatment
Patterns of curative
Comparison between clinical
medicine and community
and related factors
X-ray, other tests
Follow-up of patient
Community diagnosis &
Health & Health related
Assessment of health