vir·​u·​lence | \ ˈvir-ə-lən(t)s How to pronounce virulence (audio) , ˈvir-yə- How to pronounce virulence (audio) \

Definition of virulence

: the quality or state of being virulent: such as
a : extreme bitterness or malignity of temper : rancor
b : malignancy, venomousness the virulence of a disease
c : the relative capacity of a pathogen to overcome body defenses

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Examples of virulence in a Sentence

I was surprised by the virulence of the criticism.
Recent Examples on the Web That’s an important measure of a virus’ virulence, and a key guide to which people should be most closely watched and most aggressively treated. Author: Melissa Healy, Anchorage Daily News, "Coronavirus: 5 burning questions scientists want to answer about the outbreak," 30 Jan. 2020 In 12 countries, 196 children were paralyzed not by the wild virus, but by a strain derived from a live vaccine that has regained its virulence and ability to spread. Leslie Roberts, Science | AAAS, "Polio eradication program faces hard choices as endgame strategy fails," 30 Dec. 2019 Genome sequencing identified genes responsible for antibiotic resistance and virulence, and confirmed that the strains were related to the opportunistic bacteria that tend to be found in hospitals. Ewen Callaway, Scientific American, "C-Section Babies Are Missing Key Microbes," 18 Sep. 2019 In the future, this new resistant line can serve as a diagnostic test to assess the virulence of any new Xoo strains that crop up. Diana Gitig, Ars Technica, "CRISPR used to edit rice DNA as defense against pathogen," 30 Oct. 2019 But NotPetya’s virulence wasn’t contained by national borders. Andy Greenberg, WIRED, "The WIRED Guide to Cyberwar," 23 Aug. 2019 Like the outbreak of AIDS in the 1980s, polio’s eruption caused fear because its vectors of transmission were poorly understood, its virulence uncertain, and its repercussions unlike other illnesses. Alexander B. Joy, The Atlantic, "Candy Land Was Invented for Polio Wards," 28 July 2019 And this particular bias has infected contemporary political analysis with a virulence that rivals Ebola. Elizabeth Spiers, The New Republic, "Beyond Pelosi," 24 July 2019 These strains arise when the weakened live virus used in the oral polio vaccine (OPV) mutates and regains its virulence. Leslie Roberts, Science | AAAS, "Surging cases have dashed all hope that polio might be eradicated in 2019," 10 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'virulence.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of virulence

1617, in the meaning defined above

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Time Traveler for virulence

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The first known use of virulence was in 1617

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Statistics for virulence

Last Updated

12 Feb 2020

Cite this Entry

“Virulence.” Dictionary, Merriam-Webster, Accessed 24 Feb. 2020.

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More Definitions for virulence


vir·​u·​lence | \ ˈvir-(y)ə-lən(t)s How to pronounce virulence (audio) \

Medical Definition of virulence

: the quality or state of being virulent: as
a : relative severity and malignancy ameliorate the virulence of a disease
b : the relative capacity of a pathogen to overcome body defenses — compare infectivity

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