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How a long-forgotten virus could help us solve the antibiotics crisis

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    Take a moment and think about a virus.
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    What comes to your mind?
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    An illness?
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    A fear?
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    Probably something really unpleasant.
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    And yet, viruses are not all the same.
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    It's true, some of them
    cause devastating disease.
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    But others can do the exact opposite --
    they can cure disease.
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    These viruses are called phages.
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    Now, the first time I heard
    about phages was back in 2013.
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    My father-in-law, who's a surgeon,
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    was telling me about a woman
    he was treating.
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    The woman had an injury,
    required multiple surgeries,
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    and over the course of these,
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    developed a chronic
    bacterial infection in her leg.
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    Unfortunately for her,
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    the bacteria causing the infection
    [unclear] would not respond
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    to any antibiotic that was available.
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    So at this point typically, the only
    option left is to amputate the leg
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    to stop the infection
    from spreading further.
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    Now, my father-in-law was desperate
    for a different kind of solution,
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    and he applied for an experimental,
    last resort treatment, using phages.
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    And guess what, it worked.
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    Within three weeks of applying the phages,
    the chronic infection had healed up.
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    Where before, no antibiotic was working.
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    I was fascinated by this weird conception.
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    Viruses curing an infection.
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    To this day, I am fascinated
    by the medical potential of phages.
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    And I actually quit my job last year
    to build a company in this space.
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    Now, what is a phage?
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    The image that you see here was taken
    by an electron microsope.
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    And that means, what we see on the screen
    is in reality extremely tiny.
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    The grainy thing in the middle
    with the head, the long body
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    and the number of feet --
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    this is the image of a prototypical phage.
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    It's kind of cute.
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    (Laughter)
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    Now, take a look at your hand.
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    In our team, we've estimated
    that you have more than 10 billion phages
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    on each of your hands.
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    What are they doing there?
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    (Laughter)
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    Well, viruses are good at infecting cells.
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    And phages are great
    at infecting bacteria.
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    And your hand, just like
    so much of our body,
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    is a hotbed of bacterial activity,
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    making it an ideal
    hunting ground for phages.
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    Because after all, phages hunt bacteria.
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    It's also important to know that phages
    are extremely selective hunters.
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    Typically, a phage will only infect
    a single bacterial species.
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    So in this rendering here,
    the phage that you see
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    hunts for a bacterium
    called staphylococcus aureus.
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    Which is known as MRSA
    in its drug resistant form.
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    Causes skin or wound infections.
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    And the way the phage hunt
    is with its feet.
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    The feet are actually extremely
    sensitive receptors
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    on the lookout for the right surface
    on a bacterial cell.
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    Once it finds it,
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    the phage will latch on
    to the bacterial cell wall
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    and then inject its DNA.
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    DNA sits in the head of the phage
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    and travels into the bacteria
    through the long body.
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    At this point, the phage
    reprograms the bacteria
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    into producing lots of new phages.
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    The bacteria, in effect,
    becomes a phage factory.
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    Once around 5,200 phages have accumulated
    within the bacteria cell,
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    the phages are then able
    to release a protein
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    that disrupts the bacteria cell wall.
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    As the bacteria bursts,
    the phages move out
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    and go on the hunt again
    for a new bacteria to infect.
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    Now, I'm sorry, this probably
    sounded like a scary virus again.
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    But it's exactly this ability of phages --
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    to multiply within the bacteria
    and then kill them --
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    that make them so interesting
    from medical point of view.
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    The other part that I find
    extremely interesting
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    is the scale at which this is going on.
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    Now, just five years ago,
    I really had no clue about phages.
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    And yet, today I would tell you
    they are part of a natural principle.
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    Phages and bacteria go back
    to the earliest days of evolution.
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    They have always existed in tandem,
    keeping each other in check.
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    So this is really the story
    of yin and yang,
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    of the hunter and the prey,
    at a microscopic level.
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    Some scientists have even estimated
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    that phages are the most
    abundant organism on our planet.
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    So even before we continue
    talking about their medical potential,
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    I think everybody should know
    about phages and their role on earth.
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    They hunt, infect and kill bacteria.
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    Now, how come we have something
    that works so well in nature,
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    every day, everywhere around us,
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    and yet, in most parts of the world,
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    we do not have a single drug on the market
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    that uses this principle
    to combat bacterial infections?
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    The simple answer is
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    no one has developed
    this kind of a drug yet.
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    At least not one that conforms
    to the Western regulatory standards
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    that set the norm
    for so much of the world.
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    To understand why,
    we need to move back in time.
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    This is a picture of Félix d'Herelle.
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    He is one of the two scientists
    credited with discovering phages.
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    Except, when he discovered them
    back in 1917, he had no clue
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    what he had discovered.
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    He was interested in a disease
    called bacillary dysentery,
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    which is a bacterial infection
    that causes severe diarrhea,
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    and back then was actually killing
    a lot of people.
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    Because after all,
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    no cure for bacterial infections
    had been invented.
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    He was looking at samples from patients
    who had survived this illness.
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    And he found that something
    weird was going on.
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    Something in the sample
    was killing the bacteria
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    that were supposed to cause the disease.
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    To find out what was going on,
    he did an ingenious experiment.
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    He took the sample, filtered it
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    until he was sure that only something
    very small could have remained,
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    and then took a tiny drop and added it
    to freshly cultivated bacteria.
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    And he observed
    that with a number of hours
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    the bacteria had been killed.
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    He then repeated this,
    again filtering, taking a tiny drop,
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    adding it to the next batch
    of fresh bacteria.
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    He did this in sequence 50 times.
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    Always observing the same effect.
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    And at this point,
    he made two conclusions.
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    First of all, the obvious one,
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    well yes, something was killing
    the bacteria and it was in that liquid.
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    The other one, it had to be
    biologic in nature.
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    Because a tiny drop was sufficient
    to have a huge impact.
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    He called the agent he had found
    an invisible microbe,
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    and gave it the name bacteriophage,
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    which literally translated
    means "bacteria eater."
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    And by the way, this is one
    of the most fundamental discoveries
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    of modern microbiology.
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    So many modern techniques go back
    to our understanding of how phages work.
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    In genomic editing
    but also in other fields.
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    And just today, the Nobel Prize
    in chemistry was announced
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    for two scientists who work with phages
    and develop drugs based on that.
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    Now, back in the 1920s and 1930s
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    people also immediately saw
    the medical potential of phages.
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    After all, albeit invisible,
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    you had something
    that reliably was killing bacteria.
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    Companies that still exist today,
    such as Abbott, Squib or Lilly
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    sold phage preparations.
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    But the reality is, if you're starting
    with an invisible microbe,
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    it's very difficult to get
    to a reliable drug.
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    Just imagine going to the FDA today,
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    and telling them all
    about that invisible virus
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    you want to give to patients.
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    So when chemical antibiotics
    emerged in the 1940s
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    they completely changed the game.
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    And this guy played a major role.
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    This is Alexander Fleming,
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    he won the Nobel Prize in medicine
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    for his work contributing
    to the development
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    of the first antibiotic, penicillin.
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    And antibiotics really work
    very differently than phages.
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    For the most part, they inhibit
    the growth of the bacteria
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    and they don't care so much
    which kind of bacteria are present.
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    The ones that we call broad-spectrum
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    will even work against
    a whole bunch of bacteria out there.
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    Compare that to phages
    which work extremely narrowly
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    against one bacterial species,
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    and you can see the obvious advantage.
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    Now back then, this must have felt
    like a dream come true.
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    You had a patient
    with a suspected bacterial infection,
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    you gave him the antibiotic,
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    and without really needing to know
    anything else about the bacteria
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    causing the disease,
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    many of the patients recovered.
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    And so as we developed
    more and more antibiotics,
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    they rightly so became the first-line
    therapy for bacterial infections.
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    And by the way, they have contributed
    tremendously to out life expectancy.
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    We are only able to do
    complex medical interventions
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    and medical surgeries today
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    because we have antibiotics
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    and we don't risk the patient
    dying the very next day
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    from the bacterial infection that he might
    contract during the operation.
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    So we started to forget about phages.
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    Especially in Western medicine.
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    And to a certain extent,
    even when I was growing up,
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    the notion was, we have solved
    bacterial infections.
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    We have antibiotics.
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    Of course today,
    we know that this is wrong.
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    Today, most of you will have heard
    about superbugs.
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    Those are bacteria
    that have become resistant
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    to many, if not all of the antibiotics
    that we have developed
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    to treat this infection.
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    How did we get here?
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    Well, we weren't as smart
    as we thought we were.
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    As we started using
    antibiotics everywhere:
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    in hospitals, to treat and prevent,
    at home for simple colds,
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    on farms, to keep animals healthy,
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    the bacteria evolved.
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    In the onslaught of antibiotics
    that were all around them,
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    those bacteria survived
    that were best able to adapt.
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    Today we call these
    multidrug-resistant bacteria.
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    And let me put a scary number out there.
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    In a recent study commissioned
    by the UK government,
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    it was estimated that by 2050
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    ten million people could die every year
    from multidrug-resistant infections.
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    Compare that to eight million deaths
    from cancer per year today,
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    and you can see
    that this is a scary number.
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    But the good news is,
    phages have stuck around.
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    And let me tell you, they are not
    impressed by multidrug resistance.
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    (Laughter)
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    They are just as happily killing
    and hunting bacteria all around us.
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    And they've also stayed selective,
    which today is really a good thing.
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    Today we are able to reliably identify
    a bacterial pathogen
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    that's causing an infection
    in many settings.
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    And thier selectivity will help us
    avoid some of the side effects
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    that are commonly associated
    with broad-spectrum antibiotics.
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    But maybe the best news of all is
    they are no longer an invisible microbe.
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    We can look at them.
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    And we did so together before.
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    We can sequence their DNA.
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    We understand how they replicate.
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    And we understand the limitations.
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    We are in a great place to now develop
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    strong and reliable
    phage-based pharmaceuticals.
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    And that's what's happening
    around the globe.
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    More than 10 biotech companies,
    including our own company,
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    are developing human-phage applications
    to treat bacterial infections.
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    A number of clinical trials
    are getting underway in Europe and the US.
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    So I'm convinced
    that we're standing on the verge
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    of a Renaissance of phage therapy.
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    And to me, the correct way to depict
    the phage is something like this.
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    (Laughter)
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    To me, phages are the superheroes
    that we have been waiting for
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    in our fight against
    multidrug-resistant infections.
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    So the next time you think about a virus,
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    keep this image in mind.
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    After all, a phage might
    one day save your life.
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    Thank you.
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    (Applause)
Title:
How a long-forgotten virus could help us solve the antibiotics crisis
Speaker:
Alexander Belcredi
Description:

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Video Language:
English
Team:
closed TED
Project:
TEDTalks
Duration:
11:13

English subtitles

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