Oxford epidemiologists: suppression strategy is not viable

hello and welcome this is lockdown tv from unheard.com um today we are joined by not one but two uh epidemiologists and experts to find out what the state of play is in the coronavirus pandemic um first of all we have professor carl hennigan who is the director of the oxford university-based center for evidence-based medicine and also on the line down from rome in italy we have tom jefferson uh who is also an epidemiologist part of the cochrane center which is a charity that works on improving the evidence base for medical interventions so thank you both very much for joining us you're welcome i understand that you actually are talking almost once or even more than once a day during this pandemic so you've kind of you've worked as a team already well well tom and i have been working together for about 12 years ago and we can go right back to 209 to the swine flu pandemic and subsequently throughout this pandemic we've been really interested in the evidence we've been interested in the transmission dynamics what's happening on the ground and tom and i speak daily about the issues trying to understand a lot of the uncertainties out there so let me start carl with you then with a with a kind of a bit of a broader question which is that you know you're director of the center for evidence-based medicine i mean this is what we want we want to make decisions on the basis of evidence how do you feel the medical response and the government policy response has been in terms of evidence-based medicine has this pandemic been a good period for evidence based medicine i i i think what we'll find as we go through this that this has been a period where there have been lots of issues with the production of evidence and its interpretation what people have found very difficult is to deal with uncertainty and often what really riles me and makes me concerned is when i hear people in the media or talking and saying it's without question this is what's going to happen next so i think there's been a significant problem with predictions none of them so far have been shown to be right the second area where we try and do a lot of work is in evidence synthesis that's where tom this part and we both work with cochrane but we try and review the evidence to try and understand its quality what it means in terms of informing policy and while the evidence has been produced in a way that we've never seen before for coronaviruses what a lot of it is poor quality and it doesn't help us actually inform the policies and a good area for that would be an area like masks one of the issues we've come to say is if you look at the evidence and tom can come in because he's done the reviews in this area for about 15 years now is is to say really to inform policy what you need to do is have an approach to develop high quality evidence to do randomized controlled trials and while we seemingly understand that for drugs given the recent evidence from dexamethasone versus hydroxychloroquine we we get it there but when it comes to non-drug interventions things like masks we want to throw all of the ideas of high quality evidence out the window and then use poor quality information to inform what we should do next and that's been a persistent problem over the last 10 or 12 years that we failed to address the deficiencies in the evidence for areas like masks and what we do in the wider community okay so you you brought us straight into masks there um so let me go to tom then you've been studying these uh non-medical or these physical interventions for years uh what is your view of the wisdom of requiring mask use among the wider community specifically on masks there's there's no evidence that masks apart aside from uh people who are exposed in front lines or healthcare workers that must actually make any difference but that is uh extraordinary on its own but what is even more extraordinary is that what i'm describing is uncertainty we don't know whether these things make any difference we don't know whether they make any difference by the type of agent that we're looking at uh we don't know whether the materials or anything like that the way they're fastened the length of use and so on make any difference these are non-healthcare worker settings okay so what does science usually do when there is uncertainty well science deals with uncertainty by doing experiments like carl described the randomized control trials now the time for the randomized control trials was in february march in april no longer now because the uh viral circulation is low and we would need huge numbers of enrollees to show whether to know for certain whether there is any difference with masked wearing um on mars though um i have seen studies that have been widely shared on social media that investigate the you know on the kind of physical level um how much a mask can reduce the spread of particles and um you know there is evidence that masks work in that setting isn't there even though there may not be evidence of the kind of you know sort of controlled sample style freddie we're dealing with some of the most slippery customers in the market respiratory viruses it's not just a question of the bug and the person it's also the setting which is why all these laboratory-based experiments with plumes for instance there are studies looking at the plume of droplets coming out of mask a versus mask b and so on have to be treated with extreme care what we really should be doing is our experiments trials in the population and we have to we have to do them when there's virus circulating but isn't it a matter of common sense to it at all i mean do you do you believe that wearing a face covering reduces the amount that a respiratory virus can be transmitted even though you may not have a population-wide study to prove it the problem the problem with that particular uh belief is that the one arm of a randomized control trial which was published in 2015 so one one section of the people who took part in a study in southeast asia wore cloth masks okay and they found that these cloth masks not only didn't work but actually probably saliva and secretions and the wetness made them more permeable to incoming agents so what i'm describing really is complete uncertainty from 24th of july in the uk it's going to be mandatory to wear masks in shops it sounds would i be right in saying that don't think that sounds like a necessary or wise step stereo well look the job of evidence-based medicine is to inform decision not to be the decision and this is an incredibly important point that i think a lot of people don't get when you're actually in healthcare and actually they're making decisions so both tom has been a general practitioner and and at the weekends i still work as an urgent care gp i use the evidence to inform you about the benefits and the harms so the question is if you were in policy and asked us about what are the benefits and harms we would tell you now that there is significant uncertainty any evidence that you bring to the table will be mechanistic will be weak observational evidence which has been shown over decades to have flaws so by all means people can wear masks or not wear masks policy can make the decision but what they can't do is say it's an evidence-based decision and i think that's really important and there is a real separation it seems in my mind the difference between an evidence-based decision and something which is becoming very opaque to me is science we being led by the the science the science is the mechanism the plumes but it isn't the evidence so by all means wear or don't wear your mask but the current evidence cannot reduce your uncertainty when it comes to the policy okay so if we if we move on from from masked um and carl maybe i can ask you about the the sort of wider question of the overall shape of the pandemic at the moment i mean what we see in countries across europe is that it seems to be very strongly on the way down in some countries it's sort of almost down at nil um meanwhile in america we are seeing some resurgence or what looks like resurgence in a number of states um what's your kind of overall picture of where we are in the life cycle of the pandemic well look i think it's real it's been a very interesting phenomenon from an epidemiologist's perspective the first thing is to say we have seasonal effects every year we see increases in infection illnesses and there are about 40 or 50 that we know about that causing illnesses and the predominant one that everybody's focused on has been influenza now we're seeing coronaviruses come to the fore for lots of people it seems like this is a new infection but there are seven now coronaviruses that we're aware of that are in humans what's different about this infection was the sharp uprise particularly in the number of deaths and if i take italy was very similar to uk we had a two three week very steep uprise in the deaths and here in the uk we peaked on april the 8th and since then they've been calming down today we've just had our office for national statistics number which has said for the 12th week in a row deaths have come down and actually now the number of excess deaths are below the five year average and have been so for three weeks so we are trending in a direction where we're seeing reductions in admissions reductions in critical care use and reductions in deaths but we've never seen this sharp uprise before now that's been pretty consistent in countries like spain italy belgium and here in the uk and one of the keys about the infection is to look at who's been affected and this is quite interesting because tom and i wrote about this the difference between pandemic theory and seasonal theory and in a pandemic what you expect to see is young people disproportionately affected however i think we've had in the uk now i'd have to check today but we've had six deaths in children that's far less than what we normally see in a pandemic the flip side is more than 75 of the deaths have been in over 75 year olds which fits with the seasonal theory much more so so that's an interesting observation that we first noted interested in what's come with that while we've been in lockdown and lots of people are talking about lockdown strategies has it worked has it not what we've found in the uk is that while we've been in lockdown what happened and what went wrong is more than 50 percent of care homes had outbreaks of the infection that means two or more people had the infection so while the community could transmission may be as low as five percent it's tenfold higher in care homes who've accounted for nearly half the deaths here in the uk and more than half in areas like spain so some things have gone radically wrong so that's an interesting area as well to think about in terms of where we are now just to come when you look at the usa it's really interesting because usa if you go to new york and the areas around new york new jersey they had a very similar pattern to what was happening in europe lots of sharp uprights of death but if you go to places like texas and california today in fact they have nearly as many cases as we do in the uk now about 75 but these these areas who only have three or four thousand deaths they have about one-tenth of what happened in new york so there seems to be something radically different so while everybody's looking at the cases look at what's happening with the deaths as well because the deaths are not rising like they were in march and april and there's something different happening with the virus right now that it doesn't seem to have the same virulence and the same impact on mortality so there's two things that i'd really like to just follow up on so the first is you said it see it has more the pattern of a seasonal um infection than a pandemic does that mean that the explanation for why it's come down so much in europe is that it's summer basically and we shouldn't take from that that it's gone for good it may very well like to be back in the winter well we've just we're involved at the moment one of the things we're doing at the moment is a review of transmission dynamics looking at these particular issues and we've just put up an update actually looking at this particular issue what it looks like is the stability of the virus is far less when the temperature goes up but particularly humidity seems to be important the lower the humidity actually the more stable the virus is in the atmosphere and on surfaces so when we compare to other countries what we did see in the northern hemisphere when the conditions were right rapid spread transmission and impact on deaths now it's interesting to see what happens as we move into the southern hemisphere they tend to have outbreaks now at this point their january in effect is happening right now so that's why we're seeing down below in places like australia suddenly having outbreaks that are making the viruses reappearing and that probably is to do with the stability of the viruses more so on surfaces than actually in the air the second aspect of the seasonal effect is that we are more outside more ventilation which also may have an impact to say our viral load is reduced at this time of year and that's also important then on potential virulence but does that does that mean that you're not persuaded by theories of uh greater immunity levels uh explaining the decrease because you know there's always this optimistic idea that maybe through other kinds of non-detectable immunity actually we've we're slowing the spread and the decrease seen across the northern hemisphere is is explained by community levels you don't you don't buy that well no i i think look there is quite an interest in lots of points we're now coming to it's the first thing is as we come through march and april is to say pete there is a group of people who are more susceptible at that time of year so for instance your immune system isn't as strong that's the vitamin d argument but number two is you may have had other co-infections you may have just had an infection so your lymphocytes are not primed you're not ready to fight off another infection so they're interesting aspects the third aspect is to say one of the issues we also saw if you look at the uk data over the last five years we tend to see a very bad winter so in 2017-18 we had 50 000 excess deaths that year followed by good winters so if i go back to 2019 in fact we had about 15 000 less deaths in over 85 year olds than what we expect actually so trending into this year we had a a what a bigger susceptible population in the very elderly and you might find in the country the cities and the countries that did badly they're the largest susceptible population coming into each year so i think that's one aspect to why uh the virulence is less the second is a seasonal aspect and then third is a combination of the treatments getting better which is a combination of doing some things right and stopping other things that might be hydrogenic let me go over to tom there so you've been listening to this um what's your sense of why the results seem to be getting better over time at least when you compare numbers of cases to numbers of deaths what i would say is that what we're seeing in europe at the moment is a singapore-like transmission the transmission they had in singapore in february march where they had a low-grade constant transmission amongst workers in dormitories people who who were working age so anything between 20 and 50 with very few deaths and a number of cases in italy at the moment we've got about a 200 case an average of 200 cases a day mostly imported and deaths are below two a day and there's less than 75 people in intensive care whereas in march april that was over seven thousand so it's it is a definite downward trend the zen that the role of asymptomatics and that is completely still completely and clear that people who have no symptoms or who have eventually developed symptoms so-called pre-symptomatics that's also going to be understood and as we move into the winter we have to um i think the most important thing is to have a societal debate as to what we're going to do with these influenza like illnesses all of them not just corona so um that that kind of level of transmission you talked about seeing in italy and now in the uk we're around about um i think it's 500 more more than 200 a day but still very much down on what it was and the key question really and i'm keen what both of you think of this is is that a sustainable situation um or are we getting literally a summer holiday from the this virus and that it's likely to surge up again and see some kind of second wave when the season changes there's a difficulty because we don't quite understand what will happen once the winter period is over when we start to recirculate there will be competition with other acute respiratory infections that might change the dynamics of the virus as it goes through more people you might expect to see mutations but it seems to be more stable than some of the other coronavirus it's the stars of cov1 we're not sure what happened to that virus did actually mutate to the point where it became asymptomatic carried on circulating so there are so many imponderables here that actually i think what we have to have is more the debate about how we're going to manage the risks and how are we going to manage living with this virus and i think the problem is the policy is not being clear what should we be doing to try and inform the decisions we make for instance in terms of what's the impact of locking down and these are important questions to now answer many people might say we should have locked down earlier but actually as i said fifty percent of care homes developed outbreaks during the lockdown period so there are issues within the transmission of this virus that are not clear and require four in a way to try and understand what how did we manage to transmit it in so many places when we were all supposed to be at home well surely the answer to that one is that the people who were explicitly not included in the lockdown were key workers such as care home workers so the only people who were not protected were the people who were coming into contact with the most vulnerable group yeah and so these are the issues so if you want to go forward you've got to have a real debate about how do you stop doing this so it's not just a an evidence approach it's a societal approach so what you're describing is how do you manage to seed it into care homes well there are two ways one is you discharge patients in there or the second is you have a care worker who may be low paid doesn't get paid when they're not working and is an agency one who moves across different care homes so some of these people working five or six keep coming and going so what we need to do really efficiently now is understanding those countries like hong kong where they had a deep a clear strategy to protect care homes and if you look at germany that seems to be some of their benefits lower deaths in these settings because you may be testing them every week you may be having strategies where you pay for individuals to stay in the home you may actually say this is a bubble of people who are going to isolation and really what we're talking about is about an eight-week period if you look at the period if you did it over eight weeks you'd reduce about eighty percent of the outbreaks in care homes so you need a different strategy right there and if you did that you get rid of potentially up to half the death and then suddenly you've got a different infection you can look at and then you might not go into lockdown because that's a very blunt tool what we need to do is have a debate about what are the intelligent mitigation strategies that actually can keep society functioning while we keep those that are the most frail and elderly and the most vulnerable shielded in effect if i can just um just widen the debate a little bit that's what i meant when we have to we need to have a societal debate about what we're going to do with influenza like illness with these acute response infections because everybody thinks it's influenza and in fact influenza is a very very small on average chunk of the pie uh there are several coronaviruses which circulate every winter there are several dozen other viruses that we're aware of that circulate every winter and then there's x number of unknown viruses like covered 19 like sarsaparilla 2 was up until december that we know nothing about so we have to have a clear idea as a society what we're going to do uh if somebody coughs are we going to go on to complete lockdown is is that what we is is that our way forward i mean if that if that's what society wants that's fine i guess what you're saying is let's make more kind of surgical interventions uh in areas where we can be more confident that it's going to make a difference and try and sort of roll back some of the kind of universal policies is that fair okay let me just let me just make you an example our ancestors had fever hospitals they had lazarettes they had quarantine stations some of them are still around so instead of banging everybody into into nhs hospitals possibly infectious possibly non-infectious everybody together how about separating them which is one of the first things that you learn in medical school separating the potential infectious from those who are not infectious so say strokes or somebody's had a car accident because the consequence of not separation and the consequence of poor architecture like we've got at the moment are what you have seen the transformation of hospitals into plague pits in into in in into infectious infectious foci for the whole population these are the sort of fundamental interventions that we should be looking at based on the experience of these last few months which might have been a good use for those nightingale hospitals that we built and didn't use otherwise i would have to look at the surroundings of that and the structure one of the one of the good points you just mentioned the 19gale hospital i think i think what people will say is when you know nothing about coronavirus well how can you have evidence but actually one of the keys is to watch the evidence and the data as it emerges and if you'd have been watching the acceleration of the of the admissions into hospital and the acceleration of the deaths one of the things we watch is the rate of change in effect you know you're going to get to 70 miles an hour and when you first go on the motorway you go very fast don't you and as you get near to the top your acceleration slows and that was one of the things we were watching we watched the data very clearly and about april the 11th 12th we said we've hit the peak now the problem with not following the evidence and following the modellers is that's exactly why we were building nightingale hospitals and losing focus of we should have been looking at where the most vulnerable are while we've got this acceleration is slowing we need to focus on care homes and we lost sight of that so that's one important aspect the second aspect then about the intermediate care hospitals because the nightingale is the wrong structure what you require is if people go back we'll know if people live slightly probably a bit older than yourself freddie will remember fever hospitals in the uk that they were here till about 1980s 90s they've been about 100 years in existence they were on single floors they had isolation within isolation they had staff who were trained and they did not have lift shafts up and down and that isolation within isolation said you could put a patient in there you could see them but actually everybody was protected from each other and the argument to that is it prevents nosocomial infection people going into a hospital and catching it because as tom said these are infectious folk outside and it looks like about at least 20 percent of people potentially got the infection while they were in hospital let me try to kind of zoom out and get some sort of a concrete sense is it a proportionate response to the threat and is it right to say that we now face a new normal where pretty much all aspects of life must be different in order to mitigate this threat or do you think we should be headed back towards an old normal so where the benefits of carrying on with us the current strategy are outweighed by the harms and to be honest we i think we are right there now in that point the the issue is what are you going to do from a behavior so we need to instill what do you mean by that um dr hennigan i mean because the strategy at the moment is to be relieving taking away restrictions gradually keeping high testing and and doing what the prime minister calls and whack-a-mole strategy when we see local flare-ups yeah so i give a local flare-up so for instance i give you the number one of the problems i have is is in people being clear about you're going to lock down again at what level infection are you going to lock down the reason we went into lockdown was for health services if they're becoming overwhelmed and remember in 2017-18 they became overwhelmed 50 000 excess deaths and nobody said we're going to lock down society at that point in time so this is a real debate about at what level so if in the winter we will hit epidemic levels of acute respiratory infections again forty per ten thousand eight to ten fold higher than where we are now at that point what are we gonna do and we need to be start to be very clear in our understanding of these infections the consequences and our decision-making and at the moment i'm finding it so unclear i think the the the argument that has essentially won is the kind of suppression strategy um and you know you get experts like devi sridhara who is on television the whole time in the uk who literally say zero cases is the only tolerable state and anything up to that means we have to carry on uh with these massive interventions that is now it seems to me that the win the argument that has won do you support that so um when it comes to suppression there's only one real uh it's only the virus that will have a determination in that whatever we do next unless you take a policy like new zealand which is going to say we've suppressed the virus to zero and then we're going to lock down the country forever you are going to have a problem with any strategy that defines suppression because what we've seen with this virus is it now transmitting to the southern hemisphere in the last 20203 outbreak by now in july he was in very small pockets in the hospitals in places like toronto and they managed to eradicate it in the middle of july by isolating and quarantine all staff and patients and in doing that um that suppressed it but this virus is so out there now um i cannot see a strategy that makes sense to me right now that suppression should be the viable option the strategy right now should be we have to learn how to live with this virus and and part of that is just sort of readjusting the way we think about it then you know if you're if you're making the comparison with 17 18 um flu outbreak you know we basically need to think of it like we think of other flu style respiratory outbreaks and sort of only trigger major interventions when it crosses a certain threshold of hospitalizations that we actually think is really worrying is that is that where we should be going do you think it's important to recognize within the uk if you look at the rcgp surveillance center data which is incredibly important data it's been running for 60 years it gives consultation rates every week in about 4 million population and that's why i can be very certain about where the numbers are in terms of each week here's the number of ili influenza-like illness and acute respiratory infections that data showed in the uk in the two weeks before lockdown when people were being encouraged to wash hands and there was encouragement of social distancing where we change our behavior because we recognize a threat led to a 50 reduction in acute respiratory infections so actually quite a big difference was made in the two weeks before lockdown what we're looking for is that one or two bits of society that we can change or alter that give us that extra 20 30 reduction in the infection that means then it's manageable within the hospital setting and as we learn more we can manage the disease much more effectively um tom let me come back to you then you know what do you think going on why has this become such a hugely politicized and you know the only news story in the world and all of us are changing our whole lives in response to it i am the survivor of four pandemics for official and [Music] for the other three the preceding three i didn't even realize they were going on nothing changed um perhaps people died not so many in 2009 but a lot of people died in the 57-58 and a lot of people died at 68-69 but none of the fabric of society was eroded by like it has been by the response that was mounted what worries me most and i i have to to say that is that some catastrophic were made at the beginning of this story i won't go into them because i'll probably scare the audience what scares me what scares me more than the mistakes i tell you they'll be all over the comments saying what are those catastrophic mistakes you need to you need to give us a question i have already i have already given you one mixing potentially infectious people with not with non-infectious people the need to keep infectious people complete or potentially infectious people completely separate the infrastructure not just the patients has to be separate when you're dealing with an unknown agent as this was this was one of the the the obvious um the obvious catastrophic mistakes that were made um do i see steps being taken at european level remember i am talking from italy so i have a a europe-wide perspective do i see steps being taken to learn from that mistakes from that mistake and change policies change the way we do things change the way that healthcare is delivered and most of all do i see reception structures being set up just in case there is a resurgence or even a very bad ili season caused by viruses which are not uh science clarity and the answer is no so your view is not really that people have overreacted or the governments have overreacted so much as they're putting the emphasis on the wrong kinds of interventions these sort of it's if they've overreacted i think that that is in part is understandable because the memory of uh past plagues has gone okay and for instance spanish influenza is a is a folk memory and is only uh brought out to scare people so i think that some of the mistakes are understandable what is not understandable is not having learned from them another example um kicking everybody out of hospital okay so some of them went into cairns without testing and that's not the point the point is you make space for infectious patients where in the third floor ward okay third floor which means that you have elevator shafts we know that elevator shafts with thermals are conduits of uh for all sorts of things including microbes and then you shift them from the third floor to the first floor somewhere else inside a hospital complex and the staff looking after these infectious patients mingle with other staff in the canteen here's another thing that is uh almost certainly was an accelerator why did we why did we witness this explosive um beginning of this epidemic pandemic as anybody being investigated investigating that well a few people have asked the question we've reviewed that the answers we it seems to be more to do with uh meteorology and the presence already presence on the on on the ground of the virus but we're not sure should we not be putting huge amounts of resources into investigating this so we make sure that we understand exactly what happened and we make sure it doesn't happen again or we can minimize the risk of this happening again i think what some can i it's an important point what tom makes and this is a really important what we've seen in terms of the transmission dynamics i think with the first sales outbreak in in the far east they've done a bit better job on producing field studies on transmission and so for instance we just had a recent outbreak in in a farm in melbourne one of the key things within each outbreak there should be an in-depth investigation sample should be taken not just from the infected people but from the toilets from the bathrooms investigations were you in contact were you in close contact did you share drinks what's the layout of the settings and we've done that some parts of the world have done that and they provide really interesting information so for instance in some hospital settings in china they found the virus was located most in the bathrooms in the toilet probably an area that didn't get the attention for cleaning toilets have the potential when flushed to aerosolize sasko v2 each hospital should do a sort of significant event analysis where they look into the infection and detail what went wrong and this is important the reason this doesn't happen is often because people want to find somebody to blame and this is not just in hospitals this is across the board politically it's going to be a real issue if people become defensive and don't accept we made mistakes but we need to study in them and we need a no blame culture because otherwise as we've seen around the world it's going to lock down and we're going to learn we're not going to learn what we need to understand particularly about the transmission you mentioned politics and let me kind of conclude uh this discussion with that because it has become very politicized and heated um and you know i mean i you do quite a lot of media um carl i've seen you quite a bit but i would say you don't get invited on as much uh as those professors who are giving a scarier and more um sort of um you know second wave is about to hit governments not doing enough kind of narrative do you think that's true tilt in the media towards bad news we as individuals are part of the problem because sensationalism drives people to click on and read the information so it's a sort of big circle of we create the problem because if we put the worst case scenario out there we will go and have a look so if you want a solution you've got to get people to stop clicking on this sensationalist stuff a lot of what the problem here is context people are now aware that people on a daily basis die and this morning i had an interview with the radio 4 and they said hundreds of people are dying still have coveted each week and i said well look on average 1500 people die each day in winter it goes up to about 2 000 a day and in summer it comes down to about 1200 that's a huge disparity but nobody knows that context they also don't know in under 50s for instance there are no excess deaths and actually one of the important issue is as we get aware of this information we've got to come to terms with it so you don't i mean you're you're not framing it like this but you don't think that you have a whole set of kind of opponents within the scientific community you are driving a much more simplistic narrative where the more government interventions the better the sooner they're done the more virtuous and anything shorter that is negligent and that that group is actually winning the day yeah look we've been here before it's it's it's an issue when people consider that interventions will work because of the mechanisms because they believe it works i hear that a lot i think i consider it might but actually that's a problem when you start to look at evidence there are so many examples for our history where people believed interventions worked forgetting equips that when you test an intervention it's equally likely to work and it's equally likely to potentially harm you and that's why we need the clinical trials to try and determine what works compared to what doesn't i do think there's a narrative where people want to come on and say with certainty this is what's going to happen and it actually seems to me a very simple argument yeah next winter it's going to be worse again it's much harder to sit back and go do you know what i've been looking at this for 15 20 years and i have still unsure about what's going to happen next what we're going to do is keep following the data and one of the examples i give to people is is i i sort of say the data's a bit like the weather i can tell you for about the next three or five days what's going to happen and potentially they can tell you about two weeks into the future but what you do is keep updating the evidence and the information and to reduce the uncertainty and when we do that we do come to a clear understanding that i can be more confident of saying here's some evidence it's high quality and here's the size of the effect and that's an important aspect if you actually understand what i'm saying is you would then say well if i'm going to take this intervention can you quantify for me exactly how much benefit i will derive final quiz question for both infection fatality rate this has become this kind of uh hobby horse for everybody everybody picks different numbers uh having reviewed the evidence up to now what's your best guess for what the ifr will be will have been revealed to be in let's say two years from now okay so there are two things and i i can't do this quickly but the the big thing about the infection fatality ratio it matters who you infect because there is such a huge gradient in terms of the mortality i mean right that's what i'm going to take but if you know everybody it's very difficult because if you predominantly infect the elderly you're looking at a population based fertility of about 1 in 50. if you if you did children you'd be about 1 in 2 million 1 in 3 million so by the time you've got out there and given everybody we'll be down about where we will be when we've seen the swine flu down about the 0.1 to 0.3 much lower than what we think because at the moment what we're seeing is the case fatality tom tom would you would you agree with that if we if we're going to come back to you after two years and look at the numbers do you think that sounds about right could you uh give me a number i can play from the national lottery please we did 0.1 to 0.3 is what the world health organization might say but ifr okay okay i'll write that down i'll i'll play to the national lottery now uh here in in italy and see what uh what comes up but no view you don't have a view i have a i i just i just follow the facts uh i don't i don't like to forecast the future because with responsive viruses as i've said before you can't do that okay if you look if if you look at the whole narrative the whole narrative was distorted at the very very beginning by the obsession with influenza which is just one agent in fact the two agents and nothing else existed well we're no different from now well tom and carl thank you both very very much for giving us that time i've covered a lot of ground there um and lots of food for thought so thank you for that you're welcome that was um carl hennigan tom jefferson and joining us from oxford and rome respectively covering a whole lot of ground about what the current state of the pandemic is and some really important thoughts for us to consider going forward thanks for joining you

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Keywords: Covid, Covid 19, Oxford University, New Zealand, UK, Lockdown, IFR, Pandemic, Nightingale, Flu, Swine flu, Masks, Facemasks, Freddie Sayers, UnHerd, Centre for Evidence Based Medicine, Tom Jefferson, Prof Carl Heneghan

Id: Z3plSbCbkSA

Length: 45min 48sec (2748 seconds)

Published: Sat Jul 18 2020