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NAL Agricultural Thesaurus
U.S. Department of Agriculture

Concept Breadcrumbs

Research, Technology, Methods > biological properties and phenomena > biological resistance > immunity > herd immunity
Fields of Study > immunology > immunity > herd immunity
Preferred Term:

herd immunity

Definition:
The non-susceptibility to infection of a large group of individuals in a population. A variety of factors can be responsible for herd immunity and this gives rise to the different definitions used in the literature. Most commonly, herd immunity refers to the case when, if most of the population is immune, infection of a single individual will not cause an epidemic. Also, in such immunized populations, susceptible individuals are not likely to become infected. Herd immunity can also refer to the case when unprotected individuals fail to contract a disease because the infecting organism has been banished from the population.
Concept Schemes:
NALT Full
Broader Concept:
immunity
Related Concepts:
Entry Terms:
  • community immunity
URI:
https://lod.nal.usda.gov/nalt/263906
Download this Concept:
RDF/XMLCreated 2015-10-16, last modified 2015-12-03