herd immunity
noun
: a reduction in the risk of infection with a specific communicable disease (such as measles or influenza) that occurs when a significant proportion of the population has become immune to infection (as because of previous exposure or vaccination) so that susceptible individuals are much less likely to come in contact with infected individuals
… when the percentage of people vaccinated against a particular disease drops, herd immunity begins to fail.—
Katherine Hobson
Katherine HobsonSerious streptococcal disease does seem to be on the rise, however, perhaps because invasive strains are circulating against which we have not had time to develop much "herd immunity," as epidemiologists say.—Wayne Biddle
Wayne BiddleExamples of herd immunity in a Sentence
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The oral vaccine, which was discontinued in the U.S. in 2000, is more effective at achieving herd immunity because people shed the virus in their feces and saliva, and those who don’t receive the vaccine may come in contact with the weakened viruses and develop antibodies against polio.
—Tara Haelle, Scientific American, 30 Jan. 2025
Achieving herd immunity to limit the spread of disease depends on collective effort, but many see it as a personal choice.
—Barbara A. Perry, Newsweek, 27 Jan. 2025
Hardening against embers, clearing around houses, getting neighborhoods to adopt protective measures — this is like wearing masks, practicing social distancing and achieving herd immunity.
—Stephen A. Pyne, The Hollywood Reporter, 18 Jan. 2025
Apart from Sweden, which has intentionally (and damagingly) pursued a strategy of allowing the virus to spread largely unimpeded through low-risk populations in hopes of attaining herd immunity, no wealthy country has tried to reinvigorate its economy without first suppressing the outbreak.
—Jeremy Konyndyk, Foreign Affairs, 8 June 2020
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Tara Haelle, Scientific American, 30 Jan. 2025
Achieving herd immunity to limit the spread of disease depends on collective effort, but many see it as a personal choice.
—Barbara A. Perry, Newsweek, 27 Jan. 2025
Hardening against embers, clearing around houses, getting neighborhoods to adopt protective measures — this is like wearing masks, practicing social distancing and achieving herd immunity.
—Stephen A. Pyne, The Hollywood Reporter, 18 Jan. 2025
Apart from Sweden, which has intentionally (and damagingly) pursued a strategy of allowing the virus to spread largely unimpeded through low-risk populations in hopes of attaining herd immunity, no wealthy country has tried to reinvigorate its economy without first suppressing the outbreak.
—Jeremy Konyndyk, Foreign Affairs, 8 June 2020
See all Example Sentences for herd immunity
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Cite this Entry
“Herd immunity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/herd%20immunity. Accessed 13 Feb. 2025.
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herd immunity
noun
: a reduction in the probability of infection that is held to apply to susceptible members of a population in which a significant proportion of the individuals are immune because the chance of coming in contact with an infected individual is less
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