Which of the following is an example of herd immunity?
A) Brucellosis is no longer found in farm animals in the United States.
B) If 70% of the population is immunized against polio, the disease will be essentially absent from the population.
C) Federal law requires that all cattle not immune to anthrax be destroyed.
D) All farm animals used for food must be immunized against all the common agents of disease that infect humans.

Question

Quizplus · Accepted Answer

Herd immunity occurs when a large portion of a population becomes immune to a disease, either through vaccination or previous infection, which in turn provides indirect protection to individuals who are not immune. In this case, if 70% of the population is immunized against polio, the disease will be essentially absent from the population due to the high level of herd immunity.

Which of the Following Is an Example of Herd Immunity