4. Theories of disease causation
Germ theory
Epidemiological triad
Multifactorial causation theory
Web of causation
Devers epidemiological model
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6. Germ theory
According to this theory, there is one single specific cause forevery disease.
This refers to one to one relationship between the causative agent and
disease.
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18. Spectrum of disease
It is the graphical representation of variation in the manifestation of disease.
At one end of disease spectrum are subclinical infections, which are not
ordinarily identified and at the other end are fatal illness. In the middle of the
spectrum lie illness ranging from severity from mild to severe.