Some diseases such as influenza are contagious and infectious.
Infectious diseases can be transmitted by as, by hand to mouth
contact with infectious material on surfaces, by bites of insects or
other carriers of the disease, and from contaminated water or food
(often via faecal contamination), etc. In addition, there are sexually
transmitted diseases. In some cases, micro-organisms that are not
readily spread from person to person play a role, while other
diseases can be prevented or ameliorated with appropriate nutrition
or other lifestyle changes. Some diseases such as cancer, heart
disease and mental disorders are, in most cases, not considered to
be caused by infection, although there are important exceptions.
Many diseases (including some cancers, heart disease and mental
disorders) have a partially or completely genetic basis.
HEALTH-DISEASE SPECTRUM
The transition from health to disease, or from disease to health
is not abrupt but gradual: it occurs through stages or phases.
These stages constitute the health-disease spectrum. At one extreme
is the optimum, ideal or positive health, a state of health beyond
which no improvement is possible. Next is the stage of 'sub
optimum' health. A person in this stage is healthy and has no
pathological abnormality, but his condition is capable of
improvement
Third is the stage of 'subclinical' disease. An individual in
this stage no doubt is diseased; but there is nothing that matters
with him. The physician who examines him clinically fails to detect
any abnormality. The disease is capable of detection with the aid
of laboratory tests. The sub-clinical stage may be absent in the
cases of some diseases.
From the subclinical stage, the person may revert to sub
optimum health, or, on the contrary, pass on to the fourth stage
called the 'over' stage. The disease is now at its zenith. A diagnosis
can be readily made on clinical examination.
The last, the most undesirable, stage is that of advanced disease.
The disease is now at its worst; also often it is associated with
complications. Beyond advanced disease is the realm of death.
Infectious diseases can be transmitted by as, by hand to mouth
contact with infectious material on surfaces, by bites of insects or
other carriers of the disease, and from contaminated water or food
(often via faecal contamination), etc. In addition, there are sexually
transmitted diseases. In some cases, micro-organisms that are not
readily spread from person to person play a role, while other
diseases can be prevented or ameliorated with appropriate nutrition
or other lifestyle changes. Some diseases such as cancer, heart
disease and mental disorders are, in most cases, not considered to
be caused by infection, although there are important exceptions.
Many diseases (including some cancers, heart disease and mental
disorders) have a partially or completely genetic basis.
HEALTH-DISEASE SPECTRUM
The transition from health to disease, or from disease to health
is not abrupt but gradual: it occurs through stages or phases.
These stages constitute the health-disease spectrum. At one extreme
is the optimum, ideal or positive health, a state of health beyond
which no improvement is possible. Next is the stage of 'sub
optimum' health. A person in this stage is healthy and has no
pathological abnormality, but his condition is capable of
improvement
Third is the stage of 'subclinical' disease. An individual in
this stage no doubt is diseased; but there is nothing that matters
with him. The physician who examines him clinically fails to detect
any abnormality. The disease is capable of detection with the aid
of laboratory tests. The sub-clinical stage may be absent in the
cases of some diseases.
From the subclinical stage, the person may revert to sub
optimum health, or, on the contrary, pass on to the fourth stage
called the 'over' stage. The disease is now at its zenith. A diagnosis
can be readily made on clinical examination.
The last, the most undesirable, stage is that of advanced disease.
The disease is now at its worst; also often it is associated with
complications. Beyond advanced disease is the realm of death.
0 Comments