'Preventing pandemics at the source – stopping spillover' with Prof Peter Hudson

good afternoon everyone my name is Charles Godfrey I'm the director of the Martin school and it's an enormous pleasure to introduce Pete Hudson this evening it's a pleasure for two reasons first of all Peter's a superb scientist and also he's a very old friend we've known each other for they want to admit how long we've known each other Peter's currently the Willamette professor of biology at Penn State University and before that was uh well when he moved to Penn State was director of the Huck Institute of Life Sciences in Penn State but pizza bread first degree at Leeds defil here and then worked at the game Conservancy followed by University of Sterling and it was when working at the game Conservancy he started working on a classic problem in British ecology which is why the red grass Cycles in a regular uh in a regular manner there were various theories for it at the time but Pete showed pretty conclusively that interactions with a parasitic nematode was if not the major one of the strongest drivers of these cycles and then after moving to Penn State in 2001 Pete continued working on Wildlife disease issues building one of the strongest groups in the world World in this area the center for infectious disease Dynamics and branching out from grass to work on a menagerie of different systems rabbits mice bats amphibians and many others but Peter's one known not only for his experimental work but for shaping the emerging field of wildlife epidemiology Wildlife population Dynamics and beyond that also working on what on how diseases affect Community ecology so disease Community ecology and peace is also interested in uh spillovers from from Wildlife diseases to humans and the other way around so for example during the pandemic he worked on the frequencies of SARS Cove 2 in whitetail deer in North America and in addition to being a excellent scientist Peter's also a fanatical naturalist a fanatical wildlife photographer so we expect good slides Pete and is very involved in a series of conservation projects including a project helping the Maasai peoples in the masamara in Kenya and in a number of wildlife film projects Pete please come and give us your lecture [Applause] thank you very much indeed Charles I do actually remember the last time we met in Oxford because it was the day that we graduated because I finished my D fill at the same time that you finished your first degree and there's a photograph to actually prove it I was actually going to look it up and show it but then I thought that would embarrass both of us but thank you very much and thank you to all of you for coming here I'm very grateful indeed and I'm gonna well I'm very grateful to the Oxford Martin school I must say I've been here for two weeks and I've had a really good time I'm really enjoying myself I really like this way of doing interdisciplinary science trying to talk to people from other disciplines to try and see if we can find solutions to some of the problems we're facing today so I'm gonna try and sort of tackle that a little bit today but I'm going to start and give you a scenario just imagine you're walking down the Broad Street you're past Blackwell somebody comes out and they sneeze on you now three or four years ago you may well have turned around and actually say bless you not think anything more about it you're a polite person move on but you're no longer a polite person now you say what the hell where's your mask go and lock up you know quarantine stop doing this Behavior so the covert outbreak really has changed many components of our lives and it's been absolutely um confounding both the political side the social side and the way we can try and solve these problems and many of us who are looking at these sort of issues aren't so much worried about what's happening today but how is it we're going to try and stop the next pandemic because of course the covid pandemic was really a huge impact we're 1150 days in more than 700 million cases 7 million deaths and a loss economic loss in the region of 15 to 50 million trillion dollars that's huge so the real question is what how are we going to stop the next one before I start to think about that I actually want to say well was that just a rehearsal for the next big one will we actually slightly lucky with this one could it have been much worse well a case fatality rate was just one and a half percent with sarsko V1 it was ten percent and if this case fatality rate had been even just a little bit bigger we would have seen people in hospitals people dying on the streets sitting outside hospitals dying and we would have had a real tragedy on hand we were lucky children weren't vulnerable that really would have changed things perhaps associated with that Africa had a low death rate it seemed to evolve to become less virulent and than there were are amazing health workers during the whole of it and you know the vaccine world was in a really good place mRNA vaccines ready to go the most vaccine had just been done and of course the Oxford vaccine that would developed from that was in the opportunistic place to just move straight forward just really in many ways we were very fortunate the same time you could say we weren't so lucky we had asymptomatic transmission taking place short incubation period and then of course what are the consequences of long covid and then the political confusion over transmission The Who for example telling us that was an air slice till March 21 I think it was and then the whole confusions about orange about about the origin and me having to listen to Trump because I now live in America and then the politicization and the deniers and everything involved in that so my contention and what I'm going to try and tell you today is that really we can only prevent a pandemic at source what I'm going to tell you is the disease invasion is an exponential process and once it's established in the human population but many of the infections we're looking at it's very difficult to even contain it we do indeed need what I'm going to call biomedical countermeasures and I Define those as things like vaccines Therapeutics and the way we actually act against the infection to reduce suffering immortality but I'm going to talk and say that's problems with time delays make even that can containment difficult so outbreaks can become pandemics I think we've made a mistake and that we've thought about spillover really in a biomedical way and I'm going to actually tell you that it's an ecological process this is an ecological process and so it requires ecological cancer measures and what's happened is people have tended to ignore that fact and I'm then going to for the second half of my talk really try and show you some evidence to show you that I think we understand spillover and that we can do something about it so I'm going to ask three questions I'm going to ask what are the patterns we see in disease emergence what interventions do we currently have planned and then what is the process of spillover and how we're going to prevent it so what are the patterns well if you look Park back over the last 30 years nearly all of the infections that have threatened or caused problems have been respiratory viral and come predominantly from bats and come through a bridging host can I use this can you see that no I don't think you can or I can't see that you can see that so I will see if oh there's a pointer so if we look at the if we look at these viruses hendronipa SARS MERS you know and even Ebola suspected or confirmed coming from bats and many of them used into in use these bridging houses horses pigs civets camels I don't use the word intermediate hose because an intermediate host in in a parasitology is a specific host that part of that system it's an essential component of the life cycle so I tend to use the word bridging hose because I think that's what these hosts are they're taking the virus from one species into another species of course there's influenza as well and influenza of course comes from birds and I can come through pigs and by only choosing 30 years of course I have ignored HIV and you know HIV has been a tragedy seven million Dead with uh with uh sarsko V2 but HIV 40 million dead so far so um I'm still surprised how really AIDS had a such a big effect I mean I would never expect a vector-borne disease to cause a pandemic of course because you're only going to get in the places the vectors are but I do expect a respiratory disease but a sexually transmitted disease is something I sort of still wake up and think could that happen again so let's go back to this whole point about the bridging hosts why are bridging hosts important why is it that the virus comes from bats can cause an outbreak but invariably have to go through a bridging host now the predominant explanation is it's one of contact it's a root transmission Route where the bats contact a domestic animal a livestock animal a very domestic animal become infected and then because they live with us they then pass that over to ourselves and cause the outbreak my experience and my experience was limited because I've worked mostly on the hanipa viruses but in both of those cases I would say the bridging host is important for amplifying the virus so for example if I look if I go to Australia and I take blood samples from bat carers and these are people who should be exposed to many of the viruses coming from the that's that I'm interested in they're not getting exposed none of them are zero converting well just down the road horses are getting infected and people are dying and that I think is because the horse is amplifying the virus and giving it to people and so killing them so I think that that's an important hypothesis and I really think we don't put enough emphasis on understanding the dose response here and it's something I'm always rabbiting on about are are the emerging infectious diseases increasing are the real answer is we don't know we don't really have the sound data to be able to say that but what we can say is it looks as though the rate of global spread is faster and of course we have better technology to be able to identify them so it took HIV 56 years to get to the United States SARS Kobe one to six months Ebola less than four months SARS Kobe two two months Omicron seven days of monkeypox about 12 days so it is really rapid the spread and you've got to appreciate that now the mixing is such so big globally that any outbreak can result in things moving really fast now the process that I think about and this is the process because it's from my viewpoint and this is a series of papers done with uh Rayna plowright so Reyna plowright was a postdoc in my lab she's now a full professor at Cornell University and Reina basically runs This research so everything I talk about is in collaboration with Rayna and she is she is definitely the lead Pi these days so the process is one we call infect shill shed spill spread you've got to be careful when you use so many s's don't you in fact shed spill and spread and my main interest has always been in the pre-emergent problems what's happening to these viruses as the circulating in the reservoirs how they then expose themselves to humans we then see a spillover process and then we start to see emergence we see the stuttering chains in the human population we see some transients taking place we'll see an outbreak in epidemic and then perhaps a pandemic so my main focus has been on that Reservoir and spillover side and I did a paper in 2009 with Jenny Lloyd Smith who was working at our University at that time and Jamie put together some 400 papers trying to integrate what we knew about this process and he showed that in a lot of studies we knew a lot about what happened in Reservoir hosts so things like rabies we know a lot about how rabies circulates in the in the wildlife host and then we also know in some infections we know a lot about what happens in the humans so with SARS cov1 we knew a lot of details about that spread and we know a phenomenal amount with sarsko V2 of course but almost nothing about and that's still the same today with SARS cov2 I mean we know very little about the reservoir and the spillover process and that's in there so at that point I actually dropped what I was doing and said I'm going to spend the rest of my life working on this which is in fact what I've done so The Invasion process is really quite simple and to epidemiologists so what we look at a bridging host comes along or an infected host comes along there's a spillover event the virus comes from the bridging house over into the human and then that human enters a whole population of susceptibles and that's our naught that's the average number of new infections in a population of susceptibles and then what happens after that of course is ah would you hear in the news all the time and that's how the spreads through the population how it burns through is a fire burning through the their susceptible population but there are variations in that there are some individuals which are Super spreaders some individuals in fact a huge amount do you remember the case of the guy who was singing at the choir and infected 60 people in his choir because he sat at the back and then he was just spread and infected everybody and then left and everybody got infected so Arnold is quite good because it tells us a bit about the likelihood of invasion it gives us the shape of the outbreak and what we tried to do of course in uh in the covert outbreak was to try and flatten that so we tried to find ways we could push our North down and of course if you push our note down then it really increases the time that's involved so it tells us the likelihood of invasion but it does not tell us anything to do with the heterogeneity and what sort of variation we see between different hosts and this can be very important when we're concerned with Invasion so for example the number of cases involved the number of people involved in those initial hosts so if one of your hosts your initial host is a super spreader the likelihood of it getting established is much much greater of course it's it's pretty obvious but it's also important so it means there's always the possibility that even if it's difficult with a lower note it can get in and start stuttering and get away from you the speed of this invasion is Arnold does not tell us anything about and this was a huge misunderstanding during covid you have to know what the generation time is you and time and time again people when they were looking at new variants made the assumption that the generation time remained the same so for example there were people saying uh Arnold for Omicron was in the region of 18 which was absolute rubbish that's because they've made assumptions about the generation time the generation time is also important because it tells us how long we have to contain an infection before it starts getting away from us so if you look at this example here I show you three recent outbreaks Ebola flu and covid generation times are very difficult but after 35 days and I'm just assuming it takes 35 days to recognize you have an outbreak taking place you can see with ebola you only have 10 people infected flu you have 10 to the fifth so you might be able to contain Ebola but it's going to be very difficult to contain a flu or a covert outbreak and of course if you were to say well we could get vaccines out in a hundred days and that's not just a random figure that's the figure that the Rockefeller Institute are trying to do at the moment then you can see that the number of people even if you had your vaccine already produced and ready to go you really have the pop is really getting away from you hence I'm trying to sort of say it's very difficult to prevent a pandemic from taking place of course our outbreaks are exponential and it's something that is perhaps often sort of ignored but they do multiply very very fast if we log transform that what actually takes place is that many of the stochastic things and I'm quite interested in those occur within the first three to five generations after that it's deterministic it's gone so if we're going to be able to do anything we really have to try and catch it as soon as possible but we have huge problems with that politically because with things like biological cancer measure we have time delays there's the political issues there are the deniers there's the switch in between don't wear a mask wear a mask don't wear a mask wear a mask and then we have all the regulatory problems when you're trying to produce a vaccine which can be really difficult and give you huge time delay so even though I think the vaccine industry did a fantastic job it was very it was almost too late it had gone totally out of control so I'm just sort of Starting by saying outbreak's exponential the short generation time means for to even contain it is difficult and there are multiple time delays so there are huge challenges in there and so uh I think we need some countermeasures that are based at source now before I move into that I just want to ask what interventions do we have planned at the moment what are the things we're going to to prepare respond and prevent the next pandemic so now I'm going to sort of just move into what other people are really saying I see there are three ways of doing this there's the pre-emergence way it what can we do to stop it getting from Wildlife to us and historically that has been habitat destruction Slaughter bridging hosts and vaccination of the reservoir host and you know it's amazing things like control of rabies by people like Sarah Cleveland by vaccinating the dog host has been really quite remarkable I still find it amazing that cattle vaccination against rinderpest despite the abundance of animals in East Africa still eradicated that you can then try and contain it and control it and of course we use Trace test and treat and we can quarantine or we can try and sort of reduce this spread and the suffering with vaccines antivirals and Therapeutics so what are people and particularly people with money started to talk about this well Bill Gates was the first to come out with this book how to prevent the next pandemic I couldn't find a single line in there where he actually said how he was going to prevent the next pandemic nothing he never thought about any proactive prevention that's going to stop trying to stop spillover taking place he talked about better tools better tools for genome sequencing he had this Global epidemic response to mobilization unit with 3 000 experts doing surveillance and data integration absolutely great better tools vaccines within six months obviously you know the development to new platforms and things there's huge amounts that can be done and they're really important and they need to be done the bill they're not going to prevent the next pandemic as far as I can see given where we are at the moment and then of course uh Jeremy Farah who has recently moved from being direct to the welcome foundation and now gone to be the science director at the World Health Organization he's talking about uh also talking about better Tools in his book investing in infrastructure he's uh he thinks there's a real need for sound financial footing and he talked about a number of other things but nothing in the proactive prevention the Rockefeller Institute moved in quite fast set up their pandemic Prevention Institute appointed Rick bright and put it talking about sums at 10 to the 8th to 10 to the 9th the dollars um nothing on prevention it was mostly about looking for crucial data gaps but also huge initially all about genomics and vaccines things that need to be done important things that we need to be known as biomedical countermeasures but my whole point is they're not really going to stop a pandemic unfortunately this is sort of folded now and they've moved that into their climate Institute and so they're sort of keeping the people there Briggs moved on but they're keeping their people there but the pandemic Prevention Institute now no longer exists and he sort of said it was because there's so much competition in the field we don't need to do it but I don't believe that um and then within the past week 10 days who have come out with their zero draft an international instrument on pandemic prevention preparedness and response and here for the first time we see some words that could be involved in proactive prevention for the first time they start talking about one Health and if you read between the lines maybe what if one Health really and they don't Define it but if one Health is really about environmental health it's about Wildlife Health livestock health and so human health there may be that interaction could do something I think it's at the moment that's as far as they've gone they haven't really thought about it any deeper because they're very worried about achieving Equity they're worried about making sure the right transparency is there and that we're doing the right sort of things so of course they could things could still change but that's the first opportunity I've seen I was excited when the independent panel on pandemic provincial and preparedness and response came out because I thought that looked like a great group of people but once again they had nothing on proactive prevention and it was the sort of usual things stronger who access to final financial resources and I was disappointed because the right honorable Helen Clark is somebody I admire hugely I just think she's a great intellect she just does really good things and when she was asked directly why the report didn't include anything on spillover her response was it's like boiling the oceans and I was devastated because it clearly meant that they hadn't even thought about it they hadn't even thought about what processes could be done and I think it's fair to say that throughout the public health sector most people think that spillover is unpredictable and unpreventable and I'm not surprised because they don't think of that in an ecological way so that's what I'm going to do now I'm going to try and introduce you to emergence as an ecological process so yes Charles this is one of my photos emergence as an ecological process what is that process and how could we prevent spillover from taking place we'd have a real problem undertaking research on spillover for two reasons first of all knowing where it's going to occur and secondly being able to get replication you know we think with SARS Kobe 1 and SARS Kobe 2 there was only one spillover well maybe two spillover events with SARS cov2 with a boner we know there's like 44 and I've worked quite some time with Vincent Munster who works on it out there but he it's really difficult to know where and when it's going to actually happen and then getting in there and getting your equipment so we decided that we were going to focus on the hinipa viruses and Nipa viruses because both there's been a reasonable number of spillovers that was the primary reason to do it and of course the coming from bats so the dominant hypothesis throughout is that stochastic and hierarchical inter-specific transmission happens to drive spillover now another way of looking at that is that it is essentially a random process and you know my really good friend Eddie Holmes always always said to me you'll never be able to do it it's just that it's just happens to take place since then Rayner and I add our colleagues of the bat one Health and there are several other hypotheses but I don't think there's any data for them in either way but I'm going to tell you about our hypothesis which is that land use induced spillover at is the disruption of habitat critical to the reservoir host displaces the host to novel habitats where they shed virus and pass that to susceptible bridging hosts or to humans the idea being that habitat disruption climate disruption interact they disrupt the food the hosts are displaced and this is separator from all the other hypotheses and the hosts then move into these situations where they contact bridging hosts in humans so they move out of their natural habitat and they move into a habitat where they've essentially contact humans that's a big that's a big difference to what everybody else says so let me start by telling you the story about Hendra virus case study I'm going to go back to 1994 and this guy Vic rails he was a horse trainer in Hendra which is just where the airport is if you've ever flown into Brisbane so you actually land in hindra when you fly there and he was very famous for this horse which is called ver Rogue and he was at a race one day he came home and one of his horses at pasture a mayor that was a pasture was showing some neurological disorder it was frothing at the mouth it was choking it was not in a very good way it looked as though it had covered and what he did which was the right thing he brought it into the stable and he rang that in the vet who was on uh call at the moment who happened to be a friend of mine Peter Reed Peter Reed came over and horse was really bad and he had to euthanize it there and then over that time of course that horse died there were 21 horses on Vic's stable that were got involved 14 of those actually died Vic himself got infected and had to be rushed to hospital and he died and his stable hand got very sick and was taken into emergency care but he survived they took the samples from Vic they sent them off for analysis and identified a new virus which was the Hendra virus and it's killed Willow more over a hundred horses since then with a case fatality rate of 75 percent that's big you know covered one and a half percent horses 75 with people case fatality rate of 57 percent all the meeting amongst the horse owners to tell him what was going on and to tell them and he said he'd looked everywhere could not find what the reservoir host was it sampled everything he could find in the fields in around fixed house and then one of the horse owners said have you ever been out at night and done it and he goes what do you mean he said there are huge numbers of bats going over so then uh um he then passed that over to Hume Fields I'm sorry it was seen Our Moment human Fields then went out and started sampling bats and he found it in present in many of the bats and these are the sort of five main bat species I'm talking flying foxes the big big lovely bats I'll show you them in a minute and there are four species the black flying foxes has got the green distribution the red dots are where the spillover and they're the main species and then the gray-headed flying foxes uh trip is polycephalus down here are the blue species and they also get it as well but I got so excited by bats because they are just so different from other animals they really are remarkable animals and I think of myself as a naturalist but the life expectancy given their body size is well off the scale absolutely incredible they have more than 4 800 coronaviruses they have a robust interferon response to our RNA viruses they have a remarkable anti-inflammatory response of course being a flying species and all the things they do they have to have very good DNA repair systems they are just really different from everything else you do and it was that that really attracted me in the first instance to come and look at them their space use is nothing like you expect they will get up and they will fly a thousand kilometers to visit a tree that's in flower and there it is pumping out the nectar and they will feed themselves silly like a five-year-old child and then they will rush around as if they're having a sugar burst you know they're just like a five-year-old child they're just amazing then they'll turn around and come back again what they're really looking for particularly during the winter months are a relatively small number of species five eucalyptus trees which come out and flower during the winter months and they come out every winter except for when there is disruption from the oceanic Nino situation so what happens then is we see a cool phase happening in Australia so there's this difference in temperature across the Pacific and because of that Australia ends up with a huge amount of rain and uh and not very nice low temperatures and because of that the flowering trees stop producing and at that stage the um the flying foxes the bats stop feeding go into sort of starvation phase normally under normal conditions they're very nomadic they will go huge distances as I said but they will live in camps with hundreds of thousands so these camps are really quite remarkable and the sky almost goes black as the flying out at dusk just because of the large numbers of them within the colonies within the camps the males defend branches and then the females come and hang out next to them and you could I don't have to think I can don't have to point out which is the male there I think it's obvious but they uh and then once the female if a female lands he basically gets access to her and tries to get a mating and things like that most if not all of the hendras spillover occurs during that winter months when there are food shortages available we monitor the amount of um Hendra coming out of these backs via urine samples so because bats hang upside down all the time they can't pee when they hang in there so they have to turn themselves upside down and you'll see this individual on the right is actually urinating you'll see the drops coming out of the back and you know when they're urinating because they turn as I said they turn up the other way around quite sensible not to pee on yourself really although there's this sort of mist of urine in these colonies which I always think it's a Mist a virus and you know as somebody who's interested in transmission you think how the hell is transmission taking place is it actually taking place by one urinating on another and then they lick it off and they have to get sufficient dose or is it just this this huge mist of urine out there and where they're sucking in the virus what are the and we're able to go around and put plastic sheets out underneath it and collect the urine as he hits it and then to run samples on that and what our data shows is that if the best predictor for spillover is the viral load which brings me back once again to dose so it's not the prevalence it's the viral load that we're actually seeing in the samples so let's get back to my hypothesis and apply it to the Hendra spillover system so the hypothesis if you remember is that there's habitat disruption that should interact with climate or could interact with climate giving you food shortages and then the bats are displaced and they move it into horse Fields then when they move into horse Fields they're feeding on poor quality food where they chew it spit it out and then urinate on the pasture and horses because of the way they breathe and graze and they suck up all this virus they become infected and horses are just one of those animals like pigs that when they get a viral infection it's just it's just Dreadful it's just a huge infection one of the Vets told me that when I was with him looking at some of these places visiting these different cars he said at this place the horse had it I rushed in and the owner was just about to open the horse's mouth and I had to because they thought the horse is dying from swallowing its tongue and he said as soon as anybody opens the horse's mouth they just get a face full of the virus and that's how the humans get it and that's where the whole idea about dose sort of came from that's why I love going out in the field to do these sort of things so how do we test that hypothesis well I'm going to tell you how I wanted to do it in a minute but what we did do is we went out and studied the Flying Fox ecology for 25 years this remarkable field biologist called Peggy EB despite not having funds has in this part around eastern Australia which is where Brisbane is you might recognize it going down as far as Sydney it certainly goes down that's the Gold Coast because that's uh um New South Wales and Queensland they're the division and she went and regularly counts all of the bat roasts she records as their location when they move how many go to those places she records reproductive output because you can see the babies hanging on the females and then we were recording the spillover events and the winter flowering pulses and so getting an estimate of food shortages what Peggy's data show very nicely is that there are two periods there's a period of stability which is on the left and that period of stability is when the number of bat Roots remain constant and it remained constant until 2002 after which it then increased so between 96 and 2002 the Orange Lines show you periods of food shortage and even though there were food shortages the bats did not fission and go into smaller roasts during this whole time period the number of bats remained constant but after 2002 we saw a change in the situation that when there was a starvation period a food shortage period the bats fissioned and we saw more roosts take place and every time there was a food shortage so we saw more fissioning even though the number of bats so that over the time period we saw it go from 100 roasts to 300 roosts what was more was we were seeing the spillover events and these bat roasts taking place in different habitats so this figure shows you the change in the percentage forestry percentage Agriculture and the urban areas but in these Agro urban areas on the left and the red dots are the spillover events that's where it was taking place we didn't see very many spillover events in the forest where the bats really should be hanging out but because the starving they're moving into these urban areas where they're feeding on things like tangerines and figs and they're not on the flowers that they really want to feed on and it seems to us that what's happening is they're moving over there to um try and take advantage of these foods and in so doing coming into contact with the horses as the bridging hosts so this is the critical figure that really sums it up so initially there's the period of stability on the left the number of bats are remaining constant this shows you the ocean the Oni index and when it goes above 0.8 that means the conditions are such that we should see a starvation take place we should see a full shortage take place so one is the climate disruption then two is the food shortage and during that period of stability you saw it being one two in 2000 we saw a full shortage event without an O and I uh prediction of that but then we saw another one in 2002 2003. after that it goes from being a double punch one two to one two three one two three where we're seeing climate disruption driving food shortage and then spillover events actually taking place and the size of those spillover events are determined by the size of these um circles so this is a classic uh a 2011. so this was one of the classic cases here's the Oni goes over 0.8 the climb the which means that the climate is really wet the trees don't come into flower the trees aren't in flower there's a food shortage the next year and because of that we see a spillover event take place in the year afterwards never did we see a spillover event take place during a time when there was productive flowering so this figure shows you once again a period of stability then the period of Rapid change the dots are number of spillover events and that and the black lines are the periods of productive flowering and we never did we see this taking place now if we take all these data and assess them in a conditional in in a Bayesian Network model then what this tells us is that climate oscillations had a positive effect on food shortage and persistently and caused this fissioning in the bats this resulted in spillover when they were in these agricultural areas but if there was a late winter flowering event then that would stop it so we think this is quite nice support for the generalizable hypothesis that disruption of habitat disruption through climate interact to influence food abundance and so displaced the hosts so they go off contact bridging hosts and then cause spin over I think this is the parsimonious explanation for why it takes place but of course we now have to start thinking about other systems could it be taking place in other sorts of systems and this is Nipa virus here and what happens with Nipa virus is it's transmitted when people drink Palm juice they come and put pots under the trees in Bangladesh where we study it with Emily Gurley just fantastic person to work with and collect the Palm juice and then drink it but the bats come along they lick it they're clearly starving and they pee at it I mean they pee in it so when they drink it they get the dose of infection uh her postdoc cliff mcgeehist and a whole series of things along to see if it works with this hypothesis we certainly get the uh bats breaking fissioning into the smaller groups we've seen massive habitat destruction there and we think that could be driving it and of course Nipa virus is one of the things we're really scared about in the future because nipavirus has been shown to have human to human transmission and I think before covid this was the virus that we were most worried about Ebola well now we're really pushing because we really don't have data on this so it's quite possible that in Guinea where we've seen massive palm oil move in there that that has uh the bats are starving because of that they're moving into the villagers and maybe that's why the Ebola outbreak took place the Spiller the initial spillover took place if we go even further and say well what about Ronaldo horseshoe bats bats I don't know why I can't say it today and they're insectivorous so they're very different everything else I've talked about up to now really have been the taropid bats that feeding on nectar the Horseshoe bats of course are insectivorous so there's a very different system there and maybe it doesn't apply but maybe it does there is evidence coming out of David Hayman's lab that in the part of Yunnan where we know or we believe that kovid originated at the bats that has high Forest fragmentation High densities of livestock High human density and these bats May well be disrupted and they may well be moving around looking for food and coming into the house but that work still has to be done but I think it's something that could be done one of the things is one of the things we've been working on in fact um Tim Colton and I submitted a paper to science on policy in this and ecological cancer measures this week is we've been thinking about what are the counter measures we could actually take to try and prevent this taking place the obvious one is to do strategic habitat restoration we know which species we want to be there and we have four or five species that we really want to put out there and they're also the same species that people involved in koala restoration and people worried about the loss of endemic birds in Australia are also worried about we know where the distribution is we know where the reliable winter habitat is and a very small proportion of that point four percent is actually protected at the moment and many of those areas are in fact the good agricultural areas but I'm so gratified when I go to Australia and talk to landowners they said yeah we'll do that on our land we'll put out small plantations and the one thing that I love above all else is that we were funded by DARPA to do this work in America so the Department of Defense gave us 11 million dollars to say we should go and plant trees in Australia I just think that's great I think that's really wonderful what I want to do but nobody else wants to do is I want to go out I mean there is a problem with doing uh doing all of this and that is it's going to take 15 years before we even see the first floor so that's a ridiculous time delay we can predict we've been we've shown it we've published it before outbreaks have occurred we've shown that we can predict outbreaks we can predict spillover events taking place so if we can do that we could go out and do short-term feeding experiments I find it very easy when I go around the tropics because I take sugar water and a hummingbird feeder and I put it up and within minutes I can have bats bats coming in and feeding off those I think it'll be relatively simple to set up feeding stations around eastern Australia to do it in a replicated randomized way okay okay we predict this time next year we're going to have spillover events there and there so we're going to do treatments controls reverse them do the whole business get the replication up there because I think we need the right metrics but uh I'm a sold voice in that this choir at the moment and I'm going to keep pushing this one until somebody sees the light because I think we need to be able to show that ecological countermeasures really do work we just got to go out there and show it and I think that's the way we do it at the end of the day what I'm really after is a balanced portfolio you know I don't want you to think for a minute that I'm anti-vaccines or anti-therapeutics absolutely not all I want to do is try and recognize the biomedical cancer measures need to be balanced with ecological countermeasures I think the work and all credit to Reina for leading this work she's been absolutely superb she's given us the view where we have these insights into spillover we can predict therefore I think we can prevent so the public health notion that it's unpredictable enough preventable I would say is being refuted and there's a I don't know if you've read Christy's book Chris is in the audience thanks Chris but one of the lovely things that Chris does in his recent book which is called remind me go I'll make it easy for me you won't the title of your book and it's called the big health plan thank you the great health dilemma I beg your pardon for forgetting it I should have written it down I thought I was gonna my case with me because it's in my case of course it is I get take it everywhere but in that book Chris does this very nice way of looking at it and sort of saying there's an insurance policy approach we need for emerging diseases you can't just ensure you correct me afterwards you can't just enroll for one disease we need to ensure for all of it and then by having that shared risk it becomes an insurance basically approach and I'm going I'm proposing this is one of the ways we can cover many emerging diseases it also has the huge benefits of mitigation against climate and biodiversity loss I have to say that was my primary reason for doing this work at the beginning I am really interested in how we can prevent biodiversity loss and of course it's equitable as well I could do the quick cost benefit analysis and if you say this pandemic cost us 30 30 000 billion the ecological costs for doing this are in the region of 28 billion the benefit ratios there is extraordinary and quite acceptable and I've been looking at trying to find Alternatives and the who approach to coving in fact Kovacs vaccination for a low and middle income countries is also in the same sort of order of magnitude so I think that is quite a nice way of thinking about it it's not excessively expensive it's not it's not impossible I think we can do something about it of course all the rubbish in this was by me I want to point out that Rayna was the person who really is the leader now of this and she's doing a fantastic job and just say how wonderful it is working with people like Piggy B Emily Gurley Barbara Han Dan Jacobson is helping us predict where hot spots and things are and there's a lovely group of Charles thank you very much for having me thank you many thanks Pete that was uh absolutely brilliant uh I'm gonna ask the first question if I may so I was a bit surprised when you said how it was 1979 yes I'm sure it was how little attention um was being paid to prevention but the whole issue about wet markets and and so yeah um and uh the consumption of wild animals yes is that not something where there's quite a lot of attention to try and prevent spillovers into humans uh I'm not saying there isn't a I put this talk together with slides and then had to cut it in for half twice and that was one of the things that I sort of um uh knocked out I mean the whole I think with the covid and the information that we had from the wet Market particularly the work uh that and I've forgotten her name the personal I think of her name in a minute uh did fantastic stuff there showing us that I that you know the evidence is that it really could easily have come through there and yes of course Wildlife trade is immensely important there I mean it's just almost a no-brainer I feel silly sort of saying it do you know what I mean yeah um just to warn people that the letter is being live streamed so when you ask a question to just realize that let me go to the first question right at the back sorry Clara that's right foreign and those of you listening online please use the button to ask questions remotely thanks for a really fascinating talk um do you need to know that genetic sequences of viruses circulating in wild animal populations in order to perform these ecological countermeasures so I don't think we have to know them but I think if we're going to understand and I think if we're going to get insight I mean I've been in research I've seen well since 1979 so that's whatever it is 44 years and time and time again I am shocked at how I think a system is incredibly complex but when I actually get to understanding it how simple it really is that's why everything I've published is boring and obvious but what I'm working on today is really really cool but I think it's good to know that I think it's good to have the insights I think when we're looking in the human population the genomic sequencing is really telling us where we've been that's insightful of for understanding the processes and things it doesn't necessarily tell you where you're going to go I do think breakthroughs in serology are immensely important and I do believe very strongly in really what the Oxford Martin school is trying to do which is trying to integrate multiple techniques multiple approaches multiple disciplines to try and solve these big problems and these these very difficult problems so I think we do need all of that but sometimes I think we're just a bit stupid thank you uh Chris at the front and then do wave when you want to ask a question I'll do Chris and one from the live stream and then the gentleman there thanks very much Peter thanks for the book plug first of all um but I I'm going to check on the way in I'm I'm still one of those people that believes that spillovers are essentially unpredictable uh if you look at all of the big pathogens that you spoke about right at the start of your talk Ebola H1N1 HIV they were all essentially unpredictable so what I get from your presentation is this wonderful beautiful calibration of the Hendra system and possibly the Nipper system and that allows you to predict or repredict something that's already happened because you've characterized the essentials of that system but how do you apply that idea more generally to predict essentially the unpredictable you don't know what the basic we don't know what the primary hosts are going to be and if I can just come and if I could just come in there uh Nick Wilcox says can you can your approach protect against unknown pathogens a similar question too similar question so this is a slide done by my colleague Dan Jacobson and he works for the Oak Ridge and what Dan is doing here is he's predicting hot spots for environmental disruption and he does this through through a three-way correlations and then does it daily I think it is as sort of predictions are actually made I was really and so first of all I can actually quite say well most of those problems in the Arctic and Antarctic those those that we can ignore because those aren't the sort of places we're going to see emerging diseases but I can look at bat distribution I can look at an number of other factors and start to focus in in it and I was really gratified when I first saw it because I said Dan let show me exactly what's happening in east of Australia and he said that is definitely a hot spot s another one in Bangladesh and a couple in other places so I think we can spatially say these are the sort of we could quite easily and Dan's working on this at the moment but say where it is we should be looking and how we should be doing this surveillance and then I think that's taking us a step forward I don't think it's totally unpredictable I think we can do that I think this could be done and with technology now I think we could do it really well but I think you really have to decide where you're going to go and look and don't look at it don't look in a hundred Haystacks in 100 fields for the single Needle start saying okay the haystack we need to look in is that and it's going to be in the left hand side is like that having said that I think the ecological countermeasures are still a very good approach to take I just love the ideas planting trees for human health [Music] biologist here in Oxford um I'm halfway halfway with you but not completely anything though that um can be argued to pull up more trees obviously a positive things so that's a great a great thing to support So yahendra Nipper story is a is a nice one but you know I'm paralleling some of the comments before I am I do a lot of work in West Africa on Ebola and I can tell you that probably in a 10 kilometer radius of miliendo the spillover village there are no Palm plantations there are definitely in the prefector of geckadoo but they're done there so I think there's definitely an element of unpredictability but you could definitely classify it as a risk area yeah so I mean looking at your heat map there that covers a lot of the globe and we can't be there all the time but surveillance systems and Rapid Diagnostics can help and Rapid Diagnostics is also a major key issue is that we are seeing a minority of pillows that actually occur because to actually be on a map you've got to a there's going to be a clinical signal to get people to go there you've got to have advanced molecular Diagnostics if not sequencing and you've got to catch the pathogen in the ACT yeah so we are working slightly in the dark yeah and predicting um the next epidemic pandemic who does this pretty well I was part of the committee in Geneva in 2018 where we predicted that the most likely cause of the next epidemic was going to be a respiratory pathogenic coronavirus um but and then there's other eight other pathogens that we we also selected as high risk so what the world is doing now is not trying to make one vaccine to one virus that's going to make vaccines that will cover a Genus if a family would be too much but this may be a genius and we know maybe the top eight risk viruses and families and juices that are there it's not easy but it might do some good but really do appreciate not just making vaccines medical accounting measures it's actually preventing the spillovers uh in the first place or getting there really early and then try to isolate thank you so thank you for your comments I I think and I do I I agree with almost everything you've said I certainly don't want to try and say it's working in Ebola I do and I I think I'm with you totally because it's not just about the biomedical countermeasures and if you just uh grasp the fact that there are ecological issues associated with spillover that would need to be addressed I think I've succeeded thank you thank you very much for the dog it was very informative and it's hard provoking in a way um so I'm not a virologist I'm a bacteriologist I have a question about what are your views on re-emergence of viral outbreaks such as the one which we are seeing right now for the Marburg virus in Ghana uh what can be The Logical counter measures for the re-emergence of such viral outbreaks well I think there are there are things I didn't talk about so um there so for example uh so there are I think I just want people to think more openly than they've been thinking about and I was very disappointed with the gates and Jeremy's book and a number of other things I just felt that they hadn't really thought outside the box enough and so with luster fever for example people are talking about using transmissible vaccines and releasing those into the mice to control the vaccinate the mice transmissible vaccines could work with bats particularly if they spend a lot of time allo grooming each other and you know if they and if that could be passed through year in they could be passing the vaccine so that animals could vaccinate it and um quite a large section of my work and Charles referred to some of that was developing ways that animals could automatically use Antelope some things to treat them so I think there's a there's a huge way of looking at that and I'd be really happy to talk to you more about that and try and see ways of thinking about it and I'm here or in biology every day for the next two weeks so and at my office is just there and also having a glass of wine after the talk oh yeah that's the line that's it thanks thanks very much you you were not very enthusiastic about uh vectors as agents to increase the transmission and and uh for pandemics but I I mean I think that um perhaps with first of all climate change which which may change the distribution of vectors but also vectors as an initiating uh step and of course the greatest pandemic that affected human populations was yesinia pestis a plague yeah and we it looks as if what happened there was a climate change changed the distribution of rodents and their flea vectors but probably what then drove transmission amongst humans in Europe was human to human transmission yes and so it was initiating Factor vectors may still be very important um for that and I just wonder whether being so certain about vectors not being critical is is wrong in this in this situation perhaps not not necessarily for the whole world but at least as initiating factors so I hope I have I didn't um put that incorrectly so my point was that I don't think vector-borne disease is going to cause a pandemic because very few people in the world are are exposed to one uh to one vector however I do agree with you that there are some real issues that we need to consider with vectors and I've done quite a lot of work on those particularly tip-borne diseases but one of the things I'm I was really fascinated with zika was that zika can be transmitted of course we think of it as Vector Bond But there again we know it can be sexually transmitted it's transmitted by sexually it's transmitted in multiple ways and I think one of the things we get wrong and I gave a lecture in biology about talking biology about this last week is that we really need to think about there are multiple routes of transmission that we need to embrace so while uh in zika the outbreak may have been cause so an outbreak may be caused by a vector it's it's the actual onward transmission is through other techniques other systems and when we do the modeling we try to We tend to say oh we're going to take this model because it's about this bottle because it and that's not necessarily the right thing to do thanks can I just ask if your 28 billion is just for Australian bats no that 28 billion was globally and that was a figure I didn't come up with that was a figure somebody else came up but yes that was to tackle the wildlife trade and to do habitat restoration I'm just going to go to one online before going to the lady in the front uh this is from Harriet Bartlett is there a risk that habitat restoration could increase spillover risks at least transiently before habitat is established it is likely to have disturbance characteristics that might increase spillover risk yeah really interesting point is there could be a could be a situation there couldn't it where you could get that taking place I think it'd be really nice to do a paper on that if you want to but the Harriet is based in this building normally so she should come yeah she isn't here she obviously so I'd be I'll see you next time hello I'm a physicist so I don't know very much about this subject but I to what extent are you able to take account of political such as for example the refusal apparent of the Chinese government to give a good start to the possible launch in Wuhan of the latest of the karuna and then the rather special Reliance they had on their own vaccine and if you to that to the extent that the population which is truly enormous uh gives a large number of people with the now with the problem how are you able to do that if there can't be any Global collaboration and cooperation and freedom of data transmission if you like are you able to think about that uh I think that is something that we should definitely be thinking about and of course you're right there this huge just because this was a SARS virus it was a huge political issue in itself um I'm hoping that I'm hoping that there's who through their zero report are going to be able to do things that China will Embrace and I'm hoping that we can get to a point where we can talk about ecological countermeasures with one Health within that and that could have a big effect but I think but we have a we have a long way to go and I think the I mean my guess is that Chinese philosophy is not going to embrace environmental issues immediately but this is one of the multiple ways that we have to convince them I think I do agree it's a big issue big issue what I'm trying to do at the moment is I've set up a film company to try and and we're doing a film about a whole number of things including that's this bad word doing another film on wolves but one of the things that I'm hoping is that if we could make films that could reach the Chinese the Chinese particularly the young and things maybe we could influence them to start to really appreciate this so we have Ollie and then a question right at the back of two questions about Ollie thanks for our super talk um what do you think is driving the increasing observations or spillovers of Highly pathogenic bird flu into mammalian populations and what can we do about it oh I think oh gosh that's a bit unfair coming into me on bird flu um uh uh yes there's lots we need to do yeah I haven't really got my head around fluid at this moment I was thinking about Oedipus but um uh yeah so there is I think there are lots of things we can do and I really think we should be using new technology and I don't think we're using these new serological techniques I'm very Pro this idea of having an observatory for serology and things like that but I'm not very keen on just just did the firearm of the world because I don't think that tells us that much thank you Mike thank you very much for that talk um whilst I'm like some others in the room have um implied I'm a bit unsure about the generalizability or generalizability of the story from Hendra into others ecosystems I do think the idea is absolutely intriguing and particularly the idea of intervention based on the other the fact that you might be able to predict a year or more in advance of what might happen you suggested this idea of feeding and substituting for the trees not flowering and I was just interested in what the major objections to that have been um so I wanted her to convince you that an ecological need was was required I think the met and showing it in Hendra virus with some evidence from Nipa virus only takes us some of the way and I'm totally with you I think the you know the jury's out for all the other infections what I'd like to do is get the big funding to go and examine those so I'm not uh I'm I'm not trying to convince you that it's the solution to everything I'm just saying this is where we're at but it's this whole idea of balancing the biological and ecological countermeasures now your the question which was about how why aren't so the other people in my group and this is about one Health Group so we brought these scientists together to do the interdisciplinary work to do everything from the virology to understanding how people respond to bats and things like that and I've been pushing this ever since the data came out and the rest of the group are not keen on it they just say no let's go and get more data and as somebody trained in Oxford maybe but I just think we need a killer experiment we need to go out into something so that you stand up in the back and go holy crap that's believe it now that's what I want to do or or it's it only works on a Thursday because of this but let's try and find out the truth I just I just really like killer experiment ready to go damn we've done it we can show it I think the research really needs to go through to productivity level Clara there is a question there and just while you come out as a question online from Catherine Shepherd that I'm going to slightly rephrase do you think it's conceivable using current or future Technologies well that one might be able to induce immunity against their human pathogens in the reservoir species oh yeah choosing viral vaccination and things like that so I do think that's a possibility I do think that as I said you know we talked about transmissible vaccines I think there are other ways I think that's just way out there I mean can you imagine okay we're going to release these transmissible vac rats well crikey what where's that gonna go how's that going to go and so the vaccine denials are going to go through the roof but I think there are possibilities and the things that we need to think about and what the kiwis are trying to do for um viral uh sterilization of possums might might actually be uh proof of principle of that yeah that would be cool um lady there thank you for the very uh very interesting and very thought-provoking talk so I grew up in Malaysia and I was actually around for the 1988 NEPA virus outbreak so that is forever seared in my mind and that's actually kind of what led me into epidemiology and all of that but um I have two controversial sort of opinions around some of the things you talked about the first is that a pathogen is not really unknown ever it's always in a community or a population until the world or you know the political bodies deem it worthy of being emerging so that's one thing and then the second is that I feel like with a lot of ecological destruction there's a lot of lack of consideration or courtesy towards populations that live already in that area um and so you know there's a lot of political buy-in that's needed both from governments but also corporations thinking about palm oil harvesting and all of that my question for you is in the work that you've done have you worked with indigenous peoples and Indigenous populations and sort of considered maybe you know some of their oral histories and just their interactions with the pathogen um over over time and how that's sort of impacting spillover events now so very very interesting questions um and I I like your uh comments about Nipper and then about pathogens and I agree with you I I remember I remember some colleague in a department I was um producing a paper I said I've just discovered this new lizard and the people on the island were discovered go you didn't Discover it it's the first time you've found it it's been here all along and absolutely correct you know that's absolutely right uh very interestingly as Charles said at the beginning I really love working with indigenous people and I'm working with people in the Himalayas and as Charles said Maasai at the moment a number of other places but that's that's just such fun working with them and getting that local knowledge and things um so yes but I hope not in a situation where I could ever publish it you know that I'm doing that more for fun and I'm trying to see it through their eyes so for example we've just done a fit I've just done a film with a somebody's become a really close friend who lives up in the himalay a snow leopard the eyes of of the ladaki people and the uh people on the Tibetan the nomads on the Tibetan plateau and they do the filming they do everything and then they show us their story rather than the BBC Nat Geo coming in and going hey look at this it's amazing and he was one of the guides for them that's why he got so pissed off by it and I met him in a literally met him in a bar and he he and we started talking and he said I'm so fed up with these people coming and doing this so I I love your sentiments and I wish I'd done more for it so talking about meeting in bars okay we have run out of time I know there are a couple of people who wanted to ask people now make certain if you can come a drink that you chat to him really fun thank you so much indeed [Applause]

Channel: Oxford Martin School

Views: 1,178

Keywords: oxfordmartin

Id: efoIvBBRDGM

Length: 75min 41sec (4541 seconds)

Published: Wed Feb 15 2023