Definition of epidemic in US English:



  • 1A widespread occurrence of an infectious disease in a community at a particular time.

    ‘a flu epidemic’
    • ‘So children were dying in very large numbers from epidemics of infectious illness.’
    • ‘The U.S. government is preparing for a global flu epidemic.’
    • ‘The foot-and-mouth epidemic sweeping Europe and causing the cancellation of numerous race meetings will not affect Spain's bullfighting season.’
    • ‘The current cholera epidemic sweeping the nation needs the urgent attention of both authorities and the affected communities.’
    • ‘Is the government capable of preventing a bird flu epidemic?’
    • ‘I remembered hearing about the cholera epidemic which had struck just before I was born.’
    • ‘As a result the country's cholera epidemic continues, with more than 140,000 cases since August 2000.’
    • ‘Although scattered outbreaks occurred earlier, the first major yellow fever epidemics in America broke out during the 1790s.’
    • ‘Doctors there were seeing many cases of diarrhoeal disease and feared epidemics of dysentery and cholera.’
    • ‘Some Indian tribes experienced epidemics of measles and influenza, with infant mortality rates reaching 50 percent.’
    • ‘Vaccination is currently below the level needed to avoid epidemics of measles - a potentially life-threatening infection.’
    • ‘Between 1555 and 1559 an influenza epidemic swept through the lowlands of England and Wales and killed around 200,000 people.’
    • ‘Well below sea level, it suffered from floods and devastating yellow fever epidemics.’
    • ‘So, you might not be aware there's a problem unless a virus epidemic occurs.’
    • ‘In recent weeks an epidemic of measles broke out.’
    • ‘The worst scenario for the current SARS epidemic would be if it stormed into China's vast rural areas.’
    • ‘The ship's cook came down with the mumps and an onboard epidemic occurred.’
    • ‘The hugely controversial contiguous cull of livestock to combat the foot-and-mouth epidemic was stoutly defended by the Government.’
    • ‘They are there throughout one's lunch, determined to cause an epidemic of dyspepsia.’
    • ‘A current topic of conversation is the world-wide SARS epidemic.’
    outbreak, plague, scourge, infestation
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    1. 1.1 A disease widely occurring in a community at a particular time.
      • ‘Where resources are scarce and epidemics such as tuberculosis and HIV infection are rife, managers may see providers only as pairs of hands.’
      • ‘He likened Aids to epidemics such as the bubonic plague, leprosy and smallpox, which ravaged parts of the world in previous historical epochs.’
      • ‘Millions of Thai chickens were slaughtered to fight the epidemic earlier this year.’
      • ‘Rest assured that only on rare occasions do epidemics such as bubonic plague in India and diphtheria in Russia present a much more widespread threat.’
      • ‘This neglect contributes to the emergence of public health crises, including epidemics like HIV, hepatitis, and drug-resistant tuberculosis.’
    2. 1.2 A sudden, widespread occurrence of a particular undesirable phenomenon.
      ‘an epidemic of violent crime’
      • ‘Only some months ago, in the face of an epidemic of heroin deaths, they miraculously produced mobile vans and suddenly found extra places for addicts.’
      • ‘Oppressed groups - at least those we've talked about here - were oppressed before a heroin epidemic took off.’
      • ‘The historical cases - including the two we have worked on - suggest that ‘open marginality’ describes groups where heroin epidemics occur.’
      • ‘The idea of UV lights in public laboratories was first pioneered in Edinburgh, a city with a heroin epidemic.’
      • ‘It was around this time that the heroin epidemic in Dublin was really bad and a number of people had died.’
      • ‘It was just at the start of the heroin epidemic that laid waste to Scotland's most vulnerable estates.’
      • ‘What's behind the nation's fatness epidemic?’
      • ‘To be more specific, there is an epidemic of methamphetamine abuse.’
      • ‘The epidemic of gun violence in our society calls for some drastic solution.’
      • ‘The harshness of these practices would suggest that we are in the throes of an epidemic of school violence.’
      • ‘On the other side of the comic-coin, the Government and the police are exploring rather curious ways of dealing with the crime epidemic.’
      • ‘A few years later the heroin epidemic swept through Harlem and was devastating.’
      • ‘Now, each individual loss is a tragedy for the family, but we're not saying that there's an epidemic of crime in the United States.’
      • ‘I do not mean that the recent phenomenon of substance abuse epidemics and passive welfare has turned good health into bad.’
      • ‘Every year there seems to be a new crime wave epidemic that the media seems to play up, but six months later they've forgotten about it.’
      • ‘What she uncovers is an epidemic of unimaginable proportions within the world's most prosperous nation.’
      • ‘Hunger and oppression have spawned an epidemic of violent crime.’
      • ‘Poverty adds to the likelihood of a heroin epidemic, because it amplifies the role of the underground economy.’
      • ‘A number of approaches should be explored to combat the growing obesity epidemic.’
      • ‘We have a sudden epidemic of obesity that has emerged over the past 15 years.’
      spate, rash, wave, explosion, eruption, outbreak, outburst, flare-up, craze
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  • Of the nature of an epidemic.

    ‘shoplifting has reached epidemic proportions’
    Compare with endemic, pandemic, epizootic
    • ‘They got the message across effectively enough to stop the disease reaching epidemic proportions.’
    • ‘Typhoid fever had risen to epidemic proportions among migrant workers in the borough communities of London during this time.’
    • ‘HIV has reached epidemic proportions in India.’
    • ‘Scalp ringworm is reaching epidemic proportions in parts of Britain's cities.’
    • ‘The prevalence of obesity in the United States has reached epidemic proportions.’
    • ‘In short, humanity faces a growing global mental illness crisis of epidemic proportions.’
    • ‘Diabetes has reached epidemic proportions in this country, particularly among the Aboriginal population.’
    • ‘Diabetes mellitus is a chronic disease that has reached epidemic proportions.’
    • ‘Although Type 2 diabetes mellitus appears in almost epidemic proportions our knowledge of the mechanism of this disease is limited.’
    • ‘In the end the disease could spread in epidemic proportions.’
    • ‘The incidence of skin cancer is increasing by epidemic proportions.’
    • ‘The body louse, Pediculus humanus corporis, is a vector of epidemic typhus, trench fever, and relapsing fever.’
    • ‘During this earlier period (and to a certain extent even now), middle ear disease was of epidemic proportions in the north.’
    • ‘Diabetes is reaching epidemic proportions in Ireland.’
    • ‘A timebomb disease has reached epidemic proportions in East Yorkshire with specialists seeing more and more cases of a once-rare fatal cancer.’
    • ‘The disease assumed epidemic proportions for the first time in Taiwan in 1998, claiming 70 lives.’
    • ‘Cardiovascular disease has reached near epidemic proportions in Africa.’
    • ‘Asbestos disease is reaching epidemic proportions in Australia.’
    • ‘When a sickness reaches epidemic proportions, there is a frantic search for a cure.’
    • ‘The nineteenth century developed a number of causative theories for the finite nature of epidemic disease.’
    rife, rampant, widespread, wide-ranging, extensive, sweeping, penetrating, pervading
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A disease that quickly and severely affects a large number of people and then subsides is an epidemic: throughout the Middle Ages, successive epidemics of the plague killed millions. Epidemic is also used as an adjective: she studied the causes of epidemic cholera. A disease that is continually present in an area and affects a relatively small number of people is endemic: malaria is endemic in (or to) hot, moist climates. A pandemic is a widespread epidemic that may affect entire continents or even the world: the pandemic of 1918 ushered in a period of frequent epidemics of gradually diminishing severity. Thus, from an epidemiologist's point of view, the Black Death in Europe and AIDS in sub-Saharan Africa are pandemics rather than epidemics


Early 17th century (as an adjective): from French épidémique, from épidémie, via late Latin from Greek epidēmia ‘prevalence of disease’, from epidēmios ‘prevalent’, from epi ‘upon’ + dēmos ‘the people’.