Science: Tell me about ... E. coli O157

THE revelation that many hamburgers in commercial fast-food joints might not be sufficiently cooked to kill off bacteria such as E. coli O157 is unsettling: already, this bug has acquired a lethal reputation. It was the cause of the world's worst food-poisoning outbreak, when 19 people died in 1996 in Scotland.

So is it a superbug? Not exactly. It's a strain of the common bacterium Escherichia coli - a common organism found in the gut of man and animals and in damp, mild environments such as soil and vegetation. It can also breed in moist or wet areas in factories, untreated water, and so on. There are many types and strains of E.coli, a few of which are potentially pathogenic.

Of these, E. coli O157 (the "O" is the letter, rather than the number zero) has only been identified comparatively recently. It is also known as verocytotoxin-producing E.coli, or VTEC, because of the poison - or toxin - it produces when it colonises parts of the gut.

What seems to mark it out is that the infectious dose is very low compared to other E. coli strains - perhaps fewer than 10 cells.

Infection symptoms range from mild diarrhoea to severe, bloody diarrhoea and in some cases haemolytic uraemic syndrome (HUS) and kidney failure, which can be fatal. Most commonly, it affects children under four, but the elderly are also at risk - all the Lanarkshire deaths were among elderly adults.

It usually takes a couple of weeks for the symptoms to pass completely, but perhaps longer for the actual bacteria to be excreted.

So is it new? VTEC illness was first recognised early in the 1980s and reports of outbreaks and cases are now increasing rapidly; there have been well-publicised incidents in many parts of the world. In 1993 a large outbreak in America affected 732 people: the cause was undercooked hamburgers. An outbreak of bloody diarrhoea in a refugee camp in Malawi affecting 20,000 people is thought to have been caused mainly by VTEC, though some cases were probably caused by a dysentery-like illness. In 1996, Japan suffered an outbreak, probably from contaminated meat.

Yet tests on samples stored in the Netherlands suggest that VTEC may have been causing illness there since at least 1974. So in that sense, it's not new: but we've now got better at testing for it, and so we are noticing it much more.

In addition, the arrival of international transportation, jet flights and so on means that such bugs can be transported around the world (say, by someone who picked up a "tummy bug" in one country) and spread to new areas. Having arrived, though, there's no chance it will go away in a hurry: the modern world simply offers too many people and places where it can thrive, especially if just 10 cells is all it takes to infect someone.

How can you avoid it? Simple - use high temperatures when cooking: an internal temperature of 70 Centigrade for two minutes will kill it. And do not use the same surface for cooked and uncooked items, since that can re-infect something you just sterilised. One other thing: now, wash your hands.

Suggested Topics
peopleFrankie Boyle responds to referendum result in characteristically offensive style
Life and Style
Couples have been having sex less in 2014, according to a new survey
New Articles
i100... with this review
Have you tried new the Independent Digital Edition apps?
Life and Style
ebooksA superb mix of recipes serving up the freshest of local produce in a delicious range of styles
Life and Style
ebooksFrom the lifespan of a slug to the distance to the Sun: answers to 500 questions from readers
Holly's review of Peterborough's Pizza Express quickly went viral on social media
footballTim Sherwood: This might be th match to wake up Manchester City
Arts and Entertainment
musicHow female vocalists are now writing their own hits
New Articles
Arts and Entertainment
musicBiographer Hunter Davies has collected nearly a hundred original manuscripts
Blahnik says: 'I think I understand the English more than they do themselves'
Arts and Entertainment
Michelle Dockery as Lady Mary Crawley in Downton Abbey
TVInside Downton Abbey series 5
Life and Style
The term 'normcore' was given the oxygen of publicity by New York magazine during the autumn/winter shows in Paris in February
fashionWhen is a trend a non-trend? When it's Normcore, since you ask
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating

By clicking 'Search' you
are agreeing to our
Terms of Use.

ES Rentals

    iJobs Job Widget
    iJobs General

    Marketing Manager - Leicestershire - £35,000

    £30000 - £35000 per annum: Ashdown Group: Marketing Manager (CIM, B2B, MS Offi...

    Marketing Executive (B2B and B2C) - Rugby, Warwickshire

    £22000 - £25000 per annum: Ashdown Group: A highly successful organisation wit...

    SEN Coordinator + Teacher (SENCO)

    £1 per day: Randstad Education Leeds: Job Purpose To work closely with the he...

    Research Manager - Quantitative/Qualitative

    £32000 - £42000 Per Annum: Clearwater People Solutions Ltd: Our client is curr...

    Day In a Page

    Scottish referendum: The Yes vote was the love that dared speak its name, but it was not to be

    Despite the result, this is the end of the status quo

    Boyd Tonkin on the fall-out from the Scottish referendum
    Manolo Blahnik: The high priest of heels talks flats, Englishness, and why he loves Mary Beard

    Manolo Blahnik: Flats, Englishness, and Mary Beard

    The shoe designer who has been dubbed 'the patron saint of the stiletto'
    The Beatles biographer reveals exclusive original manuscripts of some of the best pop songs ever written

    Scrambled eggs and LSD

    Behind The Beatles' lyrics - thanks to Hunter Davis's original manuscript copies
    'Normcore' fashion: Blending in is the new standing out in latest catwalk non-trend

    'Normcore': Blending in is the new standing out

    Just when fashion was in grave danger of running out of trends, it only went and invented the non-trend. Rebecca Gonsalves investigates
    Dance’s new leading ladies fight back: How female vocalists are now writing their own hits

    New leading ladies of dance fight back

    How female vocalists are now writing their own hits
    Mystery of the Ground Zero wedding photo

    A shot in the dark

    Mystery of the wedding photo from Ground Zero
    His life, the universe and everything

    His life, the universe and everything

    New biography sheds light on comic genius of Douglas Adams
    Save us from small screen superheroes

    Save us from small screen superheroes

    Shows like Agents of S.H.I.E.L.D are little more than marketing tools
    Reach for the skies

    Reach for the skies

    From pools to football pitches, rooftop living is looking up
    These are the 12 best hotel spas in the UK

    12 best hotel spas in the UK

    Some hotels go all out on facilities; others stand out for the sheer quality of treatments
    These Iranian-controlled Shia militias used to specialise in killing American soldiers. Now they are fighting Isis, backed up by US airstrikes

    Widespread fear of Isis is producing strange bedfellows

    Iranian-controlled Shia militias that used to kill American soldiers are now fighting Isis, helped by US airstrikes
    Topshop goes part Athena poster, part last spring Prada

    Topshop goes part Athena poster, part last spring Prada

    Shoppers don't come to Topshop for the unique
    How to make a Lego masterpiece

    How to make a Lego masterpiece

    Toy breaks out of the nursery and heads for the gallery
    Meet the ‘Endies’ – city dwellers who are too poor to have fun

    Meet the ‘Endies’ – city dwellers who are too poor to have fun

    Urbanites are cursed with an acronym pointing to Employed but No Disposable Income or Savings
    Paisley’s decision to make peace with IRA enemies might remind the Arabs of Sadat

    Ian Paisley’s decision to make peace with his IRA enemies

    His Save Ulster from Sodomy campaign would surely have been supported by many a Sunni imam