02.19. Two directly transmitted viral diseases have the same
critical immunization threshold (Pc) even though their effects on
the host are different. Which of the following differences between
the two diseases could lead to the same critical immunization
threshold?

Two directly transmitted viral diseases have same critical immunization threshold and the difference between the two is described below.

Explanation:

In every three years there is an epidemic of a bacterial disease.New coyotes are continuously born into the population. Coyotes are dying from other causes over time. During an outbreak, the proportion of coyotes who are sick with the  disease slowly falls as they recover.Coyotes from other populations, who have already caught and recovered  from the disease, immigrate into the study population. One disease has a higher transmission rate and a longer recovery period  than the other.One disease has a lower transmission rate and a longer recovery period  than the other.One disease has a lower transmission rate and a shorter recovery period  than the other. For one disease, the recovery period is long; for the other.

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