Definition of virulent in US English:



  • 1(of a disease or poison) extremely severe or harmful in its effects.

    • ‘There is no question that the outbreak of SARS (severe acute respiratory syndrome) has focused the world's attention on the dangers of how easily a virulent disease can spread around the globe.’
    • ‘And on the nursing front, Alwin notes that there's been an outbreak of atypical pneumonias in Asia, possibly harbingers of a more virulent flu strain to come.’
    • ‘Their research can help head off not only the Nipah but also other virulent diseases that break out suddenly to plague man and beast.’
    • ‘Here is a woman who is trying to defeat a horribly virulent disease in rice, one that destroys millions of acres in Asia, and she's using molecular techniques to do it.’
    • ‘Both pack a virulent poison in their dorsal spines, so you must not touch anything, even what appears to be a rock, while diving.’
    • ‘Five to 15 days after exposure a pneumonia that is not very different from other less virulent pneumonias acquired in the community (outside a hospital) develops.’
    • ‘Violence and gamesmanship are a virulent virus infecting sport.’
    • ‘36 patients in five Montreal hospitals have died from a virulent infection, officials confirmed Friday.’
    • ‘However, it can produce a virulent poison called verotoxin, which attacks organs such as the kidneys.’
    • ‘The court and all those able to move into the countryside prudently did so, as the disease was less virulent there.’
    • ‘And so massive amounts of radioactivity spewed out in an invisible cloud which spread the most virulent poison all over the land.’
    • ‘An understanding of the genetic makeup of the most virulent influenza strain ever seen could help health officials manage possible pandemics in the future.’
    • ‘Not every fever or cough is likely to be this virulent pneumonia.’
    • ‘But the episode reveals how far this virulent disease has spread through the body corporate.’
    • ‘The herpes virus can be virulent, but you'll be surprised to learn that a garden herb can beat the symptoms into submission.’
    • ‘A preliminary investigation found that the symptoms displayed by the victims were similar to those caused by a virulent poison used to kill rats.’
    • ‘One little sip of this antidote would have rendered the most virulent poisons of the Borgias innocuous.’
    • ‘Mark Oliver Everett is what epidemiologists and Dustin Hoffman call a hot spot, a highly contagious carrier of an extremely virulent disease who infects anyone who crosses his path.’
    • ‘This method, the inoculation of material containing the living organism, itself was not foolproof, since it was not possible to ensure a mild rather than a virulent infection, which might prove fatal.’
    • ‘When the next human ship came the native's story of a virulent disease fatal to humans was duly noted and dispatched back to the nearest Military outpost along with the recording from the satellite.’
    • ‘Unless there was an extremely virulent strain of influenza going around, it might not be worth the risk.’
    • ‘Chinese health officials say that the strain is extremely virulent and killed one farmer in as little as two hours.’
    poisonous, toxic, venomous, noxious, deadly, lethal, fatal, mortal, terminal, death-dealing, life-threatening, dangerous, harmful, injurious, pernicious, damaging, destructive, unsafe
    highly infectious, highly infective, highly contagious, infectious, infective, contagious, rapidly spreading, communicable, transmittable, transmissible, spreading, malignant, uncontrollable, pernicious, pestilential
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    1. 1.1 (of a pathogen, especially a virus) highly infective.
      • ‘By comparison, six out of seven unvaccinated animals had to be treated for virulent malaria.’
      • ‘Concerning biotic stress, plants exposed to virulent and avirulent pathogens respond with a range of defence- and damage-limiting mechanisms.’
      • ‘Malaria, introduced after 1650, became the Chesapeake's most virulent pathogen.’
      • ‘They're seem to spread like a virulent disease.’
      • ‘So you can see that this was an exceptionally virulent virus.’
      • ‘It's sobering news that a virulent pathogen can evolve so quickly.’
      • ‘Labs are rated on a scale of one to four, four being the highest level of containment where the nastiest, most virulent pathogens are handled.’
      • ‘He said that this disease is virulent enough to kill all of the birds in a short period of time.’
      • ‘Such systemic immunity provides the plant with an effective state of acquired resistance throughout its different organs against subsequent attack by a broad spectrum of virulent pathogens.’
      • ‘I have been a virologist, and in fact I think I was the first to do any genetic work with animal viruses, and I'm very, very aware of the potential dangers if virulent viruses acting on human beings are being worked with.’
      • ‘It sparked a diplomatic incident when the ill-fated ship docked in Gibraltar leading to Spain closing its border with the Rock to ensure the virulent virus did not spread.’
      • ‘They also question whether terrorists would even try to develop West Nile as a weapon when more virulent viruses are available.’
      • ‘The paper reflects a major step forward in the study of how some of the world's most virulent viruses, such as West Nile, SARS, Ebola and Hepatitis C interact with their hosts.’
      • ‘Of course, in such enclosed confines, virulent viruses can run wild, and if the person next to you is sniffling, find another seat if you can.’
      • ‘The virus is particularly virulent for humans, horses, and gamebirds.’
      • ‘Bijerinck disproved this theory when he showed that the sap could successively transmit the fully virulent disease through a large number of plant generations.’
      • ‘When a predisposing factor cannot be identified, potential explanations include a particularly virulent pathogen or an underlying genetic predisposition.’
      • ‘This intense thriller follows the survivors of a deadly and virulent virus which wipes out London and possibly most of the world.’
      • ‘On the last days, I inoculated Joseph Meister with the most virulent virus of rabies.’
      • ‘Dr. Mackinnon said: ‘How does immune selection create more virulent pathogens?’’
  • 2Bitterly hostile.

    ‘a virulent attack on liberalism’
    • ‘Mr Duncan Smith launched his most virulent attack yet on the suspected plotters in an article in The Spectator in which he acknowledged some in the party were convinced he should not be leader.’
    • ‘In speaking to Nazi friends, I've reproached them for the virulent anti-Semitism in their societies.’
    • ‘The more virulent attacks come from Western intellectuals.’
    • ‘Ultimately this defense was transmogrified into a virulent attack on the Danish State Lutheran Church.’
    • ‘His supporters also launched a virulent attack on Kemp.’
    • ‘Hitler's anti-Semitism, virulent nationalism, and antisocialism were simply more extreme than those shared by earlier German leaders and ‘ordinary Germans’.’
    • ‘The deal was struck after days of virulent attack and counter attack.’
    • ‘Bhisham Sahni's ‘Saag Meat’ is a gentle but virulent attack on the hypocrisy that affluent middle class India continues to live its life with.’
    • ‘If you weren't contaminated before, you'll be in close contact with long-lived virulent nasties soon's you handle one of those magazines.’
    • ‘They try, judge and convict individuals who cannot defend themselves from such virulent attacks.’
    • ‘What surprised me most about that election year was the amazingly virulent attacks on Gore from the left.’
    • ‘The Washington Times and the Unification Church's Insight were among the more virulent attackers of Bill Clinton.’
    • ‘It becomes more obvious that the options the two Parties present to the electorate, offer the unenviable choice between a raging toothache, a migraine, and a virulent attack of the Farmer's.’
    • ‘Ezra Pound's virulent anti-Semitism, his radio broadcasts and tracts in support of Mussolini, stand as potent reminders of the limits and dangers of the human imagination.’
    • ‘When word came that Iron Mike had been floored by a virulent attack of the sniffles, his disconsolate well-wishers had to shuffle off without meeting their thick-necked hero.’
    • ‘You know, I think you have to take a good look at this virulent attack by Barbara.’
    • ‘For many, the combination of virulent radicalism and reasoned temperament is wholly seductive, and attacks upon Chomsky by conservatives and centrists have only granted him a martyr's aura.’
    • ‘This work thus presages the more virulent attack on the German socialists to be found in the Communist Manifesto, produced two years later.’
    • ‘Over the years, founder Ted Byfield has been particularly virulent in his attacks on the mindset that is increasingly reliant on government handouts and regulation.’
    • ‘E. A. Freeman's virulent attacks on J. A. Froude for inadequacy in using archives are similarly to be recognized as rhetoric.’
    vitriolic, malicious, malevolent, malignant, malign, evil-intentioned, resentful, hostile, spiteful, venomous, vicious, vindictive, bitter, rancorous, acrimonious, mordant, astringent, incisive, cutting, biting, scathing, caustic, stinging, blistering, searing, withering, abusive, mean, nasty, aggressive, savage, harsh, devastating
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Late Middle English (originally describing a poisoned wound): from Latin virulentus, from virus ‘poison’ (see virus).