Crowd diseases arise when
A) a formerly isolated population is exposed to pathogens that only affect non human animals.
B) a formerly isolated population is exposed to pathogens that have been in other human populations for so long that the people there are immune.
C) too many people crowd an area and sneeze uncontrollably on each other.
D) people refuse to have their children vaccinated.
E) members of isolated populations visit crowded areas, bringing unfamiliar infectious diseases.

Question

Quizplus · Accepted Answer

Crowd diseases arise when a formerly isolated population is exposed to pathogens that have been in other human populations for so long that the people there are immune. This is because the previously isolated population has not had the chance to develop immunity to these pathogens, which can then easily spread and cause outbreaks.

Crowd Diseases Arise When