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Prof Carl Heneghan: How Positive Covid Tests are Forever

Video Transcript

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hi and welcome this is lockdown TB from
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unheard and so earlier this week we
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recorded a wine raging discussion with
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Professor Karl Hennigan of Oxford
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University’s Center for evidence-based
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medicine and his colleague Tom Jefferson
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covering all sorts of aspects of the
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covered nineteen pandemic and we will be
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publishing that shortly but yesterday
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evening news broke of a discovery that
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Professor Hanigan had made in these
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statistics so we thought we’d quickly
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catch up with him and hear about that
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beforehand
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professor Hanigan thanks for doing this
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you’re welcome
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so this concerns deaths and the numbers
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of deaths that are attributed to Cobb in
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nineteen and these matters because that
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daily total that is is announced for
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deaths in England affects the whole
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atmosphere it affects whether people
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think that the pandemic is coming to an
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end or not it even affects politics for
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example it’s referred to by Nicola
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Sturgeon and neighboring countries as to
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where what border arrangements should be
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and you discovered that that daily
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deaths total may not actually correlate
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to people dying from carbon 19 tell us
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about that yeah one of the things about
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England and particularly UK is it’s
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quite confusing when you look at the
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different ways deaths that are reported
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you’ve got office for national
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statistics you’ve got public health
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England and then you’ve got NHS England
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then you’ve got the four devolved
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nations who all do slightly different
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things so it’s it’s very confusing but
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one of the things that we noticed is
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public health England grace lots of
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confusion because one day for instance
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on the six of July they will report 16
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deaths and then the next day there’ll be
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hundred and fifty-two deaths and at that
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point the media takes it but notice
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starts to get concerned and you see
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these reports of hundreds of deaths per
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day so what we did is go back and look
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at the Office for National Statistics
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who report the death who are registered
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so when you go to the register your
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death that death certificate is then
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centrally registered so they’re very
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accurate about the day they occurred and
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what we noticed if you go back for
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instance in the 30th of June the PAP
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figures put health England are about
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double
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the ONS figures so we ask questions of
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what’s going on here and what we noticed
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is if you look at the way phe does their
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reporting they are reporting anybody who
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has had a test positive for Kovan in the
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past therefore a death reported today
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could have occurred in could’ve the
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Cobra could have occurred in early March
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you may not even be related but the way
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they’re recording it it assumes that
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people are thinking oh there are over a
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hundred deaths today things are getting
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worse
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no it’s interested in the devolved
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nations like Northern Ireland and
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Scotland so just just so I’m really
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understand it so if the individual
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patient had covered 19 in March Gregg
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recovered completely was subsequently
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tested negative and then died in a
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nursing home three months two months
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later that would then be recorded as
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occurred in nineteen death that is what
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we assume is happening from a public
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health England and that’s where the
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disparity is coming from the wide
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variation interestingly if you look at
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Scotland and Northern Ireland they have
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a sort of 28-day cutoff period and
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that’s exactly what we’re asking for
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what you really want to know is what are
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the deaths occurring in the context of
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an actual test that has occurred
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positive tests in the last 28 days and
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then you can then you can understand the
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trends what’s happening and okay so k2
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report the historical deaths but
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actually they don’t help us understand
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what’s happening now now this will get
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increasingly confusing as we go into the
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next winter because you could have a new
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outbreak new death but you’d also report
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in historical deaths we may not see that
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trend in the way that they’re currently
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reporting this you know if someone had
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come in 19 now recovers and then dies of
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something completely unrelated next yeah
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in the current system yeah and that’s
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why we’re saying it looks like you can
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never recover under the current system
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because he could die of influenza for
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instance in January next year but
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because he had a positive Coby test
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you’d still appear in the figures now
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that creates a real
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problem for us as epidemiologists
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because then we get confused but not
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least the media’s getting confused so
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one of the key aspects were asking here
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is for some clarity in terms of how we
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actually do this and some joined up
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thinking between ons NHS England and
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public health England so you get one
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emerging datasets that’s consistent so
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if they fix this which kind of we hope
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they will understand they in Sweden
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there’s a similar method for counting
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carbon 19 deaths but there’s a 31-day
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kind of elapsing period and also I think
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many states in America count them in the
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same way as well and are you are you
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even happy then though I mean if there
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is if there’s a sort of period where the
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the fact of the carbon 19 infection is
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counted on the death certificate and
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that elapses odd to say a month do you
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think we’ve then got accurate numbers
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yes so there are two distinct issues you
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get into is the immediate cause and the
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immediate cause means you’ve had Kovac
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and we suggest that actually that’s
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within 21 days because that gives you a
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time where you probably still not
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recovered and you’re in hospital and you
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died outside of that it tends to be an
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underlying cause it contributed your
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death but it wasn’t the direct cause of
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your death and actually a 21 day cutoff
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would be helpful because it would give
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us a clearer understanding of that
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distinction of immediate versus
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underlying cause of death but there’s I
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mean I spoke to a GP personally who said
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that you know he’s he was going around
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certifying deaths in old people’s homes
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and you know he was encouraged to put
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over 19 on the desk if he wasn’t sure so
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you have a you know an elderly person
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with dementia who has some sniffles or
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whatever and then they say well maybe
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that was Toby 19 should we be worried
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that even beyond this technical problem
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that could be fixed there might be
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inflation of carbon 19 numbers more
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generally
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yeah and that’s important to remember
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that when we have influenza outbreaks we
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never test people and we put in
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on the death certificate because of what
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circulating at the time and there tends
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to be that conflation and an inflation
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in effect because you the sort of biases
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in you’d is that at that moment in time
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the most likely cause if you have a
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fever is COBIT that’s one of the issues
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that you see the deaths in ons are
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higher than both sets of data in NHS
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England in public health England and
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it’s contributing to some of more of the
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confusion if you like and I think this
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is incredibly important because what we
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follow then is the excess death and
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that’s the the most accurate piece of
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information that can tell you what’s
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going on at that moment in time he can’t
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tell you though what them excess deaths
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are actually caused by and we’re
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starting to see reports that some of
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them in the home setting for instance
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are a consequence of people not coming
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forward with heart attacks and that’s
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really important to understand that bit
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of information because what we know now
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is in the last three weeks the excess
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deaths are in are actually come down
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below the average for three weeks in a
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row and now that the hospitals are more
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open as well so people who go into
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hospital again yeah but not in the same
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numbers we’re still not back to normal
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we’ve still got this reticence and I
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think it’s across the board as we look
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at like going back to the office people
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are still concerned still worried and
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anxious about going to hospital because
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they perceive they’re gonna get COBIT
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when they go in to a hospital
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that’s why it’s incredibly important we
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have accurate figures that we can
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portray to the public to say this is
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exactly what’s going on today as opposed
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to what we see is sometimes in the media
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it’s going up there are hundreds of
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deaths things are getting worse when we
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look at the data and say actually that’s
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inaccurate and we don’t use the public
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health England data to understand the
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trends it’s in what’s difficult about
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this and I think why people will
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probably be arguing about this for years
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to come is that so many of these
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individuals are very elderly and many of
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them are in care homes and you know a
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huge push to test everybody in care
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homes but people also die all the time
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in care homes for obvious reasons and
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and when you’re dealing with such old
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people you know it’s gonna always be
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hard as knit to sort of disaggregate if
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someone tests positive for Kobe 19 but
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then sadly at the end of their life what
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actually is the cause of death so
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there’s an important distinction the
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difference between life lost and life
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years lost and one of the issues we’ll
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be watching very closely over the next
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six months is to watch how many people
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would have actually died in the next six
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months and so their deaths were brought
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forward by kovat because they were
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vulnerable but actually their deaths was
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their lives were shortened by a few
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months and that’s where the excess death
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calculations really matter and if we see
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significantly trendy number now for the
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next three to four months
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we’ll start to come forward with
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information that suggests yes exactly
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there was a group of vulnerable people
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who were actually any respiratory
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infection could have been influenza
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could have been covered would actually
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have shortened their life by a few
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months what’s interesting and important
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about this is that actually it’s looking
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like about 50% of the deaths are related
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to care home ties are directly in care
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homes are those people are admitted to
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hospital in places like Spain it’s as
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high as 70 percent so the number one
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mitigation strategy should be to shield
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Cairns and they should be real thoughts
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about how to do that really well because
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yes you’ve just nailed it on that
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they’re the most vulnerable to this
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infection and it seems to be once you’re
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over 85 it really is has a big impact on
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mortality in that age group when I read
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your analysis yesterday the reason my
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heart sank because I thought if we can’t
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even trust the the death numbers that
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are coming out from public health
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England every day you know it’s gonna
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make conspiracy theorists of us all in
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the end because you know it seems like
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the tilt on all of these things if there
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is room for error and of course it’s
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difficult it always seems to tilt in the
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direction of making the numbers look
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worse rather than look better we haven’t
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had these kind of ambiguities in the
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other direction
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so much and it’s it gives the impression
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that the kind of the structures are all
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pointing in one way I mean do you feel
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that yeah so that’s an important issue
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that’s going on in the media the sort of
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you’re always there about the
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catastrophe and the consequences of that
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one of the things we notice is when you
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don’t hear about something there’s
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probably good news happening so when
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Sweden looks worse you hear about it but
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when it’s not so bad like now you never
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see it in the media but I think there
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are two issues that are really important
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one is out of this pandemic I think we
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need a joined up thinking about how
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statistics are produced it was in this
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country and across the UK covered the
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devolved nations and that will help us
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understand what’s going on particularly
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this issue about immediate causes of
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death we’re having the same problem with
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testing as well we’re never quite sure
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if somebody’s been admitted where’s
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Kovac or got Kovac while they were in
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hospital and we can’t understand that
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big piece of data so that’s one the
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second is it’s incredibly difficult to
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compare across countries as well because
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deaths are all collected and collated in
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different ways simple things like the
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age reporting is different for instance
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we wanted to compare England for
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instance death rates to Island and
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Island has a much younger population
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than England so you can you can look at
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that and think how can we compare what
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would have happened in Ireland if we’d
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have had an age structure like that we
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couldn’t do it because they report their
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age bands differently to England so we
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need joined up thinking internationally
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as well so we can make clearer
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comparisons so at the moment you see
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this problem of we’re doing worse or
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better than this country but what
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actually we look at and go it’s really
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difficult to tell that given the way the
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current reporting happens and and you
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conclude this then that central number
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which is the basis of all international
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comparisons it’s the basis of a whole
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our whole understanding of this which is
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how many people have died we can’t
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necessarily have confidence in because
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the public health in the number we now
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know seems to be including people who
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have recovered the ons number which is
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comes out of death certificates seems to
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be including some people who may not
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have had it
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but certainly people who had might have
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died of other things and just had it at
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the time and then if we look at the
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excess death number that includes people
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who might have died for other reasons
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like not going to hospital so we don’t
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you know is it fair to say that the
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actual common 19 death number is likely
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to be lower than any of those official
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numbers yeah so so there are two things
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one thing we follow which has been
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incredibly helpful is what NHS England
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have done and in doing it they made a
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change to report the date of the death
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and when we look at that in hospitals
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now we’re looking at about an average of
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about 19 deaths per that day and that’s
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slightly coming down because I’m
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referring back to about five days ago
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when it’s stabilized so each day they
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report but they could go back five days
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in time so NHS England is the best
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dataset to understand the trend they
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account for 60% of the death ons is
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useful but the problem with OH&S is we
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have to go back about 10 days and wait
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till Tuesday for it to report so we
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can’t accurately tell you what’s going
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on today but we can tell you what was
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going on 10 days ago so those are the
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two data sets wheels and I tend to not
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pay attention to phe because of this
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problem with the way the data reported
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and the variation from day to day and
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and the ones that you do use you feel
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confident in at least are a reasonable
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reflection of Toby 19 deaths yeah and
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what about yeah one of my jobs is and
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our team’s job is to tell you whether
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it’s coming down or very sensitively
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when do we think it’s going up as soon
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as it’s going up we would inform and say
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look we think the trends going in the
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opposite direction it is still coming
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down it is slowed slightly but he’s
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still going in the right direction and
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that’s an important distinction because
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we also want to be able to say oh maybe
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there’s a second phase of an outbreak
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it’s changing in the opposite direction
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and that’s really important to have that
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distinction within our ability to
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understand the trends Carl Hannigan
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thank you so much for paying close
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attention to these things and there’s
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more of you coming up later all right
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thank you very much that was Professor
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Hannigan just clearing up
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what he’s
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about the ambiguities around public
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health England deaths so thanks that
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you’ll be hearing more from him and Tom
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Jefferson later today
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you