According to the natural history of disease model, the time before the precursors of disease and the host interact is called the period of: a. prepathogenesisb. pathogenesisc. primogenesisd. b and c

A) Prepathogenesis.

Explanation:

Prepathogenesis is the period preliminary to onset of disease.

For a disease to occur 3 factors are required.

1) Agent

2) Host

3)Environment

In absence of any of them disease cannot occur.

During prepathogenesis phase , man is not involved but he is exposed to risk of disease. During this phase the three factors (Agent , host ,environment) are present but in isolation forms. When these start interacting with each other man moves into pathogenesis phase.

Hence the answer to above question is A) Prepathogenesis.