The Likelihood of a Host-To-Host Epidemic Is Highest When

Multiple Choice

The likelihood of a host-to-host epidemic is highest when:

A) the proportion of immune individuals in a population is below the epidemic threshold.
B) the proportion of immune individuals in a population is above the epidemic threshold.
C) the proportion of immune individuals in a population is at the epidemic threshold.
D) anytime the proportion of immune individuals in a population rises above 50%.
E) the second time a pathogen is introduced into a particular population.