Definition of infect in US English:



[with object]
  • 1Affect (a person, organism, cell, etc.) with a disease-causing organism.

    ‘there is no evidence that the virus can infect humans’
    • ‘This tick borne spirochaete normally infects birds, small rodents, and red deer.’
    • ‘Mosquitoes that bite infected animals then bite humans typically transmit the disease.’
    • ‘Invariably, new suckers carry the pests and diseases that have infected the parent plant.’
    • ‘All it would take would be for that bird influenza virus and an influenza virus from humans to infect an animal or human at the same time.’
    • ‘Humans catch the disease though close contact with live infected birds.’
    • ‘The infection occurs as the result of a bite from an infected flea or handling infected animals.’
    • ‘If this is the only disease infecting the plant, leaves may not yellow and drop.’
    • ‘Crowding also reduces air circulation, allowing moisture to remain on plants long enough to allow fungal and bacterial pathogens to infect plants.’
    • ‘However, not all diseases have good animal models, and some pathogens will infect no other species but humans.’
    • ‘A gene from a human pathogen is inserted into a bacterium that infects plants.’
    • ‘A third example is foot-and-mouth disease, a highly infectious disease that infects cloven-hoofed animals.’
    • ‘Children can get ringworm from touching infected animals such as dogs and cats.’
    • ‘In temperate regions, adult mosquitoes arise in the spring from developmental aquatic stages and infect birds; this cycle continues into early fall.’
    • ‘The 28 deaths so far have been linked to close contact between infected birds and humans.’
    • ‘Since then, West Nile virus has spread rapidly westward, infecting birds, humans and horses.’
    • ‘The researchers also showed cats can become infected with bird flu if they eat infected birds.’
    • ‘A bacteriophage is a virus that only infects bacteria, they don't infect any human tissue.’
    • ‘Often, there is a mixing of genes from viruses that infect different species and this creates drastically different viruses.’
    • ‘The success of a pathogen in infecting a host plant depends on how rapidly the plant recognizes the pathogen and activates appropriate defence reactions.’
    • ‘Write down which plants were infected with diseases and where the weeds grew most.’
    pass infection to, transmit infection to, spread disease to, contaminate
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    1. 1.1 Contaminate (air, water, etc.) with harmful organisms.
      ‘the water was infected by cholera’
      • ‘Soil from your garden contains bacteria, noxious seeds, and possibly other harmful organisms that may infect your newly potted plants.’
      • ‘In either case, they'll die before they can infect food or water supplies.’
      • ‘Without it I wouldn't know if the area became damaged or infected, leading to possible nasty complications.’
      • ‘It is contracted by inhaling tiny droplets from water infected with the legionella pneumonia bug.’
      • ‘These produce a less pungent smell than do the diverse organisms which infect many surface-ripened cheeses.’
      • ‘Almost every area of life is a potential terrorist target - with scare stories about the threat of a smallpox outbreak, and bioterrorists infecting food supplies and water reservoirs.’
      • ‘His straw follicles are infected, besides, like he's been standing in water.’
      • ‘Bilharzia is transmitted by bathing in water infected with bilharzia larvae.’
      • ‘The crops never grew, the water became infected with disease, the creatures came out after dusk - it was dark times.’
      • ‘It is transmitted through contaminated food, water and infected human faeces.’
      • ‘Oh, and the guy who they burnt handily made it to the local reservoir, thereby infecting the local water supply.’
      • ‘There's a good chance that the meat we use in the kitchen is infected with harmful bacteria such as campylobacter.’
      • ‘Are you ever tempted to cheat, to damage the landscape further, to poison it, infect it, before you take a photograph?’
      • ‘But what are the poisons tainting our growth and infecting our sight?’
      • ‘Somewhat reassured, the group try to settle down to enjoy the rest of their vacation, unaware that the diseased man's body is face down in the reservoir, infecting their water supply…’
      • ‘Using what little water he had in his traveling water, he cleaned out the wound before it was infected.’
      • ‘Or does it become tainted by the violence that seeps through the cracks of the skeletal buildings and infects the air?’
      • ‘These will have been totally ineffective because international research shows canola pollen can travel up to 6 km to infect other canola crops.’
      • ‘Even infected farms may be able to carry out some crop operations, however, with the permission of the divisional veterinary manager.’
      • ‘Once it enters a body of water, it spreads infecting the entire body of water.’
      contaminate, pollute, make impure, taint, foul, dirty, blight, spoil, mar, impair, damage, ruin
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    2. 1.2Computing Affect with a virus.
      • ‘By comparison almost one in ten emails (nine per cent) sent out in July were infected with a computer virus.’
      • ‘If the file attachment is launched the virus infects the computer, and attempts to spread to other email addresses.’
      • ‘Usually, unless you enjoy reformatting and wiping off your hard drive, a virus infects your computer when you execute an infected file.’
      • ‘They also found many of these airport lounge PCs were infected with computer viruses.’
      • ‘Antivirus software can only protect your computer from viruses trying to infect it via email, CD-Rom, floppy disk, Word documents or other types of computer files.’
    3. 1.3 (of a negative feeling or idea) take hold of or be communicated to (someone)
      ‘the panic in his voice infected her’
      • ‘Because they are Christians who believe in creationism, and the literal truth of the Bible, they are, it seems, unfit to teach children, lest they infect them with their foul ideas.’
      • ‘Clearly, unadulterated bias contaminates many stories and can even infect the entire Washington press corps from time to time.’
      • ‘Instead, recent events have acted as a catalyst for the crisis of confidence and belief infecting the West, throwing into relief Western elites' inability to stand up for basic values like universalism and democracy.’
      • ‘It infects relationships with poisonous impulses.’
      • ‘Tom's words were infecting us all with fear and doubt.’
      • ‘He is out to remove the spectator from his normal or appropriate perceptual field, and in doing so to infect him with his own personal doubts.’
      • ‘It's a tendency that infects anybody that mistakes the Faith for an ideology (of which, more later).’
      • ‘Because an atmosphere of lies like that infects and poisons the whole life of a home.’
      • ‘Apparently it's Christmas, but the spirit has not infected me as of yet.’
      • ‘This is how this type of misinformation spreads throughout the Air Force and infects every level with a plague of bad practices that are perpetuated internally.’
      • ‘I notice the bewilderment in their eyes, and it infects me: Why, exactly, should anyone get so worked up about a piece of ice?’
      • ‘This sort of insanity had infected me when I first came to Kuwait.’
      • ‘But to be infected by the biases of survivors is to be poisoned as a historian.’
      • ‘Forget postmodernism, the emergent church may be infecting us with a real evil.’
      • ‘For this is the poison that has infected British society, and now seems to circulate in the very air we breathe.’
      • ‘The house was big, not as big as the one that had just infected her with a bad case of money envy, but still big.’
      • ‘It's boring and this sense of laziness infects me until I can barely move at all.’
      • ‘In my view those Missionaries infected us with the reading bug.’
      • ‘Here the agent's action is infected, poisoned by racial hatred.’
      • ‘Maybe her arguments are so stunning that, were I to make the effort, I would realise that I have been deluding myself and the Yanks really are the poison which infects an otherwise carefree world.’
      affect, have an effect on, influence, have an impact on, impact on, touch, take hold of
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Late Middle English: from Latin infect- ‘tainted’, from the verb inficere, from in- ‘into’ + facere ‘put, do’.