Naturally speaking, generally speaking. Hi, and thanks for listening to the latest episode of the National Speaking Podcast. My name's James Grecian. I'm joined here today with James Barkley.
Hello. We're also joined with two postdocs in the department at the Institute of Art University, Annual Health and Comparative Medicine. We've got Sony Townsend and Joe Holiday. Hello.
OK, so what we really do feel is to find a bit about what you both do, and then we'll go into a bit of detail about some of the research you've published fairly recently, and we'll hopefully go through that in a vague and coherent way. Vaguely. Vaguely. Vaguely.
Vaguely. But first, I mean, Joe, do you want to tell us a bit about your, what your role is here and your interest. OK. So I'm a postdoc here at the Institute, and I'm currently working on a project, which is a field epidemiology project based in Tanzania, but with quite a few involved and quite a few members of the department here in Glasgow.
And we're looking at the epidemiology and burden of three bacterial zenosis that people acquire through infections from livestock that they live with, in northern Tanzania. So the pathogens we look at are called brusillosis, leptosporosis and q fever. Nice. And they have to flip off the tongue.
And despite the fact that we think they impose big burdens on livestock productivity and human health, we know a lot of them and little about them and how to deal with them. OK, we'll come back to some of the terminology in a second, but I think before that we'll find a bit about what Sun does. Did you want to tell us a bit about your role of research interests and your role in development? My role.
My role, yes. So I work on the secret rabies, particularly interested in how we can design vaccination strategies better to improve the chances of eliminating this disease from countries or small regions. Placing verities. Well, I don't know.
And epidemics. So recently I've been working in a Bali in Indonesia, for me, I'm interested in the core. It's a good one, I feel safe. And so that was, they had an outbreak in 2008, and we've been involved in trying to help them come up with strategies to eliminate rabies.
Cool. So one of the things I might try and get to start with is just putting out an idea of what, when you're talking about epidemiology, we're talking about xenotic pathogens. What some of these terms mean? Because some of these terms might not be too familiar with the side theory of the zoonotic pathogens.
I think both of these are the ones we ought to be able to mean. Yeah. I'm right. So what, yeah, when you talk about xenotic pathogens, what are you talking about?
OK, so what we're talking about is pathogens and infections that people acquire through transmission from animals to people. OK, so they can focus in animal kingdom and then they transfer into people, like them just by being around them, by touching them or by eating them more. Yeah, so there are a range of options. And really what we're talking about here is multi-host pathogens, where one of the hosts is humans.
OK. And we're interested because we're obviously mostly interested in human health and life's operating in that kind of thing, often most interested in the transmission from animal populations into human population. Cool. I suppose that presents, sir.
You're going to challenge for actually trying to understand them, giving them that they can be both in humans. I imagine, monitoring diseases in humans is probably ready to be. No, it's not even easy. That isn't even.
That's very easy. Compared to trying to also find out where things are in natural populations of things, animals are like, those of you might everywhere that must be. Even more challenging. I think so.
And it's sort of led to recognition of that. It has led to a bit of a drive recently, which is called this sort of idea of what one health is, where there's a recognition that to tackle these pathogens and this sort of group of diseases, you have to be integrating across disciplines and doing animal population research, as well as human population research, as well as ecosystem research and looking at how different populations are interacting with each other as well to try and understand the transmission processes. So these really big, these one health, is this an idea sort of presented by big international bodies, the World Health Organization, or is it Glasgow-focused? Is it quite a big board?
It's a pretty big board idea. It's been around for a while, but recently there's sort of, it's been taken up, I think, prompted by things like influenza outbreaks. There's been a bit more of a drive towards it, and there's a few years ago there was a tripartite concept note between WHO, OIE and FAO, and there's a recognition that that, so yeah, sorry, OIE. Yeah, it's the World Health Organization.
The OIE which is sort of the animal equivalent of the WHO. Okay, cool. There's something French isn't it? Yes.
I don't know if I'm going to have an exit here, so I'm going to tell you what the question is that? I just wondered the way. I mean, because we're talking about some pretty nasty diseases, things like Ebola, HIV, N1, rabies, these can cause massive problems, but it can occur in large animal reservoirs, if you like. Yeah, and it's an enormous range of things as well.
So as you know, as you say, there's sort of the high profile and quite alarming and scary pathogens that people hear about in new stories from Ebola, as you say. And then you also range all the way down to the endemic things that I work on that are less high profile, but actually probably have bigger impacts and burdens on the populations that live with them. I suppose that's quite important, isn't it, that both your research interests are not in diseases that affect our problematic. That we worry about most often in the developed world, so influenza, it's more of these diseases that I think many of us forget about, and they're actually endemic and really problematic in some of the developing parts of the world.
And what are the main reasons why these diseases are so problematic, so now is it because people don't understand? Do you understand what they'd be able to do, is the lack of public health, sort of awareness or? Well, I think that rabies for when it is neglected, and that means neglected people suffer from it, not necessarily the disease, but that's neglected because people who suffer from it are sort of neglected. So the problem really is that they're not getting access to the treatment.
So for rabies, for example, the treatment exists. It's just expensive, and it's usually located quite far away from where these people actually suffer from rabies, well, suffer from potentially having rabies can access it. So that's one of the major barriers for rabies control. Because I mean, in the conflict with their frequencies, it's very difficult to report them, and I think you probably imagine the situation is a lot worse than you initially might expect.
So I don't know, do you find that often it's very difficult to actually get information about, to what extent these diseases are some problematic areas and how, what they are? Definitely, and as Sunny says, that sort of stems from the fact that all the patterns that I work on are also in this group of diseases that are called neglective tropical diseases, and as Sunny says, it's really about the neglect of the population. And because you know, these are pretty well represented within neglective tropical diseases, because they tend to affect people who depend on animals and interact with animals. So people who keep livestock are very vulnerable to the impact of these diseases being there in their lives every day, and the impact that they have on both their health and health of their animals and the productivity of the animals, which they depend upon for their livelihoods.
But these are populations who are neglected for all sorts of development and economic reasons as well. And yeah, it is difficult to gather data on them. The three things that I work on specifically, there are lots of complications about them, and one of which is that they're really difficult to diagnose clinically. So people will present with a non-specific free-brileness.
And in the absence of pretty much any good diagnostic test, it's very difficult for a clinician to face with that. So what is that? I think you've got Bruce Loses, and I'm going to treat you for it. So one of the first challenges of actually identifying, is that it's a good thing, which people will, but then find what happens in these causes.
That illness is not the way that you can't always do it, if you symptoms can, it's not the way that these areas are quite remote regions, then try to fly global experts in particular areas, is obviously not really feasible. So public health screening at the root is really important in this case. Yeah. And the study that I work on currently has been prompted by a longer term study that's been conducted in all intents, and you're looking at the febrile population that gets to hospital.
And obviously, traditionally malaria has been a big focus on in terms of, like, trying to diagnose what's causing these illnesses in people. But what this study that's been conducted over the past few years has done, is work from a basis of implementing really old standard diagnostic tests, and looking at actually, can we diagnose these cases, rather than looking at them presumptively and diagnosing them as malaria. And they find that in the population that they're looking at, that they're looking at 11 times more cases of fever, acute fever in hospitalized patients, are caused by one of the three patterns that we work on, then caused by malaria. So it's malaria, so pregnant, just everyone assumes it's malaria.
Yeah, and in the area that we work in, malaria has declined considerably over the past decade or so, and it's certainly the case of malaria remains an enormous problem in many parts of the world. But there's such a pressure on clinicians not to miss malaria diagnoses, and they don't have any diagnostics with which to make any different kinds of assessments. And it's basically people that are being treated from the area when they don't have malaria. Okay, so I suppose the key thing is that, to be able to control and prevent spread disease, you need to know which one it is, because it's not.
The same strategies are not necessarily going to apply to everything, is that correct? Or all sorts of broad strategies that can be applied to that would help, that would be beneficial for all types of genetic diseases? Well, so I guess one of the things that we're trying to work on is, thinking about this holistically and how to go around these kind of assessment processes holistically, is I'm not saying I'm going to fight for this one disease, and I'm going to try and figure out how to do diagnostics without it. I recognize that actually there are going to be lots of things going on here, and we need to think about things that are core, and that can be useful to diagnosing or dealing with lots of these different diseases.
Lots of the roots transmission of human infection are common. It's about close interaction with animals. So what can we do to intervene either at those points of contact to reduce risks of transmission of several diseases potentially, or can we prevent the shedding of these infections from the animal population, so that they're not the potential threat to the humans? Yes, I suppose in that case you're looking at ways to monitor the risk of monitoring, because monitoring is a present, but also monitoring situations in which transmission of any disease might be particularly prevalent.
It's really difficult to get people to report and get information from people who aren't getting infected or who aren't interacting with animals in place, but it's really difficult to get this information, or people quite happy to provide information on when they've been ill, and when they've been ill, and that's quite difficult here. I think it's not, I'm not aware that there are big problems of people not giving information when they're asked for it. I don't think that's the problem that a lot of these diseases are underreported, but I think there are other reasons for that. One is that often they're not asked.
People aren't aware that they should be looking for them. The difficult diagnosis, so it's difficult to write down an attributable cause for something, so it doesn't get counted. And the reporting issue, I think, sort of disease reporting on the animal side particularly, a big reason that that doesn't happen, I think, is because nothing useful happens when you report anything. There aren't great infrastructures to respond to reports.
So you're just the other way you're just telling people for no reason whatsoever? Yeah, and there isn't really a culture of doing that. When I say if it's really hard to diagnose differences in the causes of fever and people, it must be impossible to try and differentiate between different causes of illness and animals that can't tell you what's wrong with them. I think so, I'm not trying to eat the kind of side of it.
Yeah, I think that's quite complicated. So in most cases, it seems to be cases of just improved communication to make it easier to communicate, but also give the information about them when people are well aware of what they might be infected by, but also get the communication coming back the other way, the form that people are actually able to maybe diagnose these things and say, well, you've got this is this disease, in this case you might want to take these actions and examine this. And I suppose that's the missing, trying to bring all that working together is very difficult. Yeah, I suppose.
Yeah, but as you say, it is a lot of it is about communication. So one thing is about condition awareness so that you can train clinicians about awareness of the things that they might be thinking about when they see a fever or a patient in all cases. But then you can also talk to the people who keep animals and you can tell them there are some pretty basic public health messages that you can talk to people about. Like some of the things that we work on are transmitted through consumption of, say, on pasteurized milk or undercooked meat.
And those are pretty common risk factors and you can talk to people about the risks that are associated with those kinds of practices and try and understand why people do them and what the costs and benefits of different approaches of control would be for them. It might be good to go into actually explore one particular case. It might be good to look at, because if you've been able to look at areas and look at babies and study that, it might be useful to explore a bit about the issues in a more specific example. Thank you, James.
I guess it's something that's slightly easier to diagonalize at a distance. You can walk in and see what animals with the fever and what's going on. No, what's going on, but it's a walk into a village and a dog screaming and shouting and got a frothing mouth. It might be slightly more obvious that you've got kids of babies.
Well, yeah, we've picked up at the point and it is actually fairly easy to detect a dog. All those saying that some dogs will just kind of crawl under a rock and die, but it won't go out and bite lots of people, essentially transmit babies and other dogs. In that case, it will emphasize any problems they have controlling and understanding transmission of babies, it's even harder for diseases where you don't necessarily know you can't easily see an infection, you can't see the term of what it is looking at the animal person so you've got that. I suppose it's not, it's not, even if you can identify which animals have babies, you still don't necessarily get the information, people don't necessarily give you the information.
It's hard to get it, isn't it? So I'm going to refer to one of Katie's studies, and what she, well, her work, Katie Hanson. So she does some contact tracing and she basically, when someone gets bitten and they come to a clinic, she'll kind of send out or even herself, go and investigate what happened and find out all the dogs that were bitten by the dog, that person, all the other people who were bitten by the person and try and sort of exhaustively follow that trail and get a picture of the transmission of babies. She must have like built up a network of where the sources come from if you like.
Yeah, so eventually, heavy, we'd get to the tour to a source. Well, maybe that people's a dog that came from another village or something like that, but you know, trying to get a real picture of how babies could be transmitted. And not every person who gets bitten or who gets bitten will get babies, it's about a 50% chance. But identifying those dogs and those people obviously is really useful for trying to control babies and treat people.
But more, well, really interestingly, it's a picture of how babies are transmitted and sort of interesting things like how many dogs does a rabbit or a bite and anything like that. So I think that it's an interesting question, if you can get information about who you bite, so that's quite critical for actually understanding this path of transmission and understanding that path of transmission can therefore maybe help you identify, is it useful for identifying areas where you can maybe try and focus your treatments and your preventative measures and therefore try and contain the disease. What sort of methods are used to try and control and prevent the spread of babies? What can people do?
Okay, so the main way to attempt to control babies is through the mass vaccination dogs and that involves getting a dog and sticking in the net, which has its own complications. But the idea is you may like it. They don't like it, they offer it like a lot of dogs in the places that we work are not very easy to just pick up. It often requires sort of catching them.
And yeah, so in Bali, for example, their teams have been trained up to go out and catch difficult dogs and vaccinate them. Because there's really going out and caging, trapping dogs almost not quite in the wild, these are the semi-fere animals. Well, yeah, so there's an interesting concept here. What we understand is three dogs.
We've sort of grown up and say, we're not doing dogs, we're not on a leech, effectively, or we're having an obvious owner nearby. In most of the world, in most developing countries, really, it's not really the case. Most dogs, they just allow to see them. Like cats are in this country.
They're effectively equivalent. But the western world drinks are their stray and they're not owned and they go any rubbish and that kind of thing. But they actually do get fed and they do have illness. So the mass vaccination of bugs in an area, it does work, it does prevent the spread of disease.
It's been, I suppose it depends whether the area, how contained the area is. I mean, imagine if you've got a whole continent then, the mass vaccination of every single dog with a continent is pretty challenging. But imagine if you've got a smaller, more contained location, like an island, it's a strategy. The strategy is quite dependent quite a lot on where you are and what you're trying to, you know, what your aims are, I suppose.
Absolutely. No, that's a very critical. I mean, the very important concept which comes to this answer is the question which you've heard immunity. You don't necessarily need to vaccinate every single animal in order to protect the population.
And this depends on how fast the disease spread and particularly on a concept called the basic productive number. You come across the door. Oh, have you? I think I think our storm was explaining about it in the context of the film contagion.
Oh, right. And saying that's someone. I can't remember the act. Take Winslet explained that.
There's a white picture of her writing on or on a whiteboard which I use in my presentation. It's Hollywood works. You can of course tell it's an explanation. What do you mean by that?
Okay, so like we were talking about the context rating, so it's basically the number of infections caused by a case. So if I, and I bet you all here, and I transmitted it to two of you, then my, I don't know what for me, and if you scale that to a population, you take an average. We then left and started biting other people. You might be a teacher, but I'll just give you a couple of the whole...
Some people like to bite more than others, I suppose. Exactly. There's no footballers in this one. Yeah, exactly.
So for the point is for babies, it's actually really low. It's 1.2, so that's on average a dog will bite and infect 1.2 other dogs. So just above one, if it was one, it would be reproducing itself. And you can imagine...
Exactly, like a concept of population. So it increases slightly. But you need to vaccinate enough to reduce that number below one, and that's the idea of controlling disease control, a lot of the basic diseases control. And you can do that for your dog vaccination.
It's like more complicated, you need to vaccinate 70% of the population. I guess that's because if you've got a reservoir population in a certain area, you can vaccinate that, but depending on immigration and migration movements in between populations, if you vaccinate your population, then 100 dogs come over to the health of the next village. Exactly. Yeah.
And there's birth and death and so going on. So you have to take that into account. But once you take that into account, if you vaccinate 70% of the dogs in a year, in a well, this is the rate of amount of time, but the idea is vaccinate some of the dogs over in an area, and then that will keep them at an hour or below one of the disease at an hour or below one until you do the next vaccination campaign, which is going to be in the following. So is it possible to eradicate the disease?
Was it possible to keep it at a very low level? No, it's possible to eradicate. Yeah, so it just pushes it below one. But yeah, it keeps it below one.
As long as you maintain that immunity, it can't spread. Well, it's not taking too much, it can spread, but it can't increase. Yeah. Okay.
So it's on the damage direction. So I suppose the key thing is also, it is in fact, or it's not going to have to chose the surveillance of it. So you need to make sure you're given evidence of this. Because if you don't, I suppose you want to know how prevalent it is in the population, I suppose.
That's quite important for. Does that modify the type of strategy you might use to control it or? Absolutely. Well, okay, so the recommendation that, well, we've looked at it kind of different strategies, and the two kind of key big ones are sort of a proactive strategy and a reactive strategy.
And the practice is kind of blanket vaccination. You just cover the whole area. You just find like, well, every village, every dog's in every village. That's...
Versus the kind of...we know there's a case here and we go and we just vaccinate that village. What I do suggests that you need blanket vaccination. Because we don't have high enough levels of detection to be able to know that we've missed an area that's had a case, but we don't have to take to that case. And so you vaccinate somewhere else and it just really still spreads in another part of the.
I mean... So in terms of trying to understand all these methods, I mean, you used a lot of ecological modeling to try and bring to do sort of collect the data and then... Or you've just sort of put the data and parameters in and using the data to estimate various parameters between the printer model and then see what happens when you implement various sort of strategies. You've described it all with it.
Yeah, you've done concept. We use data from Katie because she's collected this amazing contact with data. And that really is what's put into the model. But we put it on to space...
Or put it on a map of barley, basically. And then we try the strategies so we can add spatial variation and where the good facts are over here or you do the reactive campaign. And then look at how that affects your prospects for illumination. And that one of the things that we were talking about earlier that I guess comes into play as a study of the property of detection.
So it seemed quite important in that paper that the earlier that you detect this outbreak, the more likely that you'd be able to react to it and try to kind of clog off shit to stop it from spreading too far. Yeah, absolutely. And knowing you've got rainvings to start with, so it's kind of like... It might take it if you've got only a 1% chance of detecting rainvings, for example, then it could take years almost before the numbers grow to an amount that you actually detected it.
And then you've got that response lag, usually it's months, potentially also years. And then within that time, it's an exponentially increasing burden. And then eventually when you actually start in front of control, you've got a really bad situation in your hands. Yeah, there was again, a body that was quite slow, everything was quite slow too.
It was one day we think they had about 7,000 rabies case of dogs on the island. And by the time they actually started implementing any kind of mass vaccination coming. I mean, it's the other you guess in theory potentially the cheaper costs are actually rectifying the problem. If you're going to try and kill 7,000 dogs and then vaccinate the rest of the population, it's quite expensive.
Whereas you can get that first 10, 20, 100 cases, the cost overall. The cost, yeah, the cost of down and the time they can illuminate it and chance of illuminating it and not turning it to endemic diseases. I suppose it's part of what I was saying earlier, these sort of glo, having a system of basically which we ought to carefully want to arrange things. If you set up a very very easy to set up a separate system for monitoring and keeping an eye on it, then it would be, I imagine, virtually impossible, isn't it?
I'm not unfamiliar with this, but I imagine we've thought about a few small subset of possible genetic diseases. Yeah, one of the things we talked about in the paper that we referred to earlier on, we've thought about the ways that you can think about what you need in terms of surveillance for outbreaks of new infectious diseases. And how you can think about that and reconcile them with what you also need for surveillance of endemic diseases. Because there's quite a lot of interesting moments of global surveillance of outbreaks of things.
And if you think about how you're going to set up a system for a developing country to tell you when this new thing arrives, what are you going to train those people to do and what are they going to do whilst they're waiting for whatever that is to happen? And how will you know if that system works whilst you wait? And what we argue is that actually the thing that you should do is sort of have a group of people who are doing the surveillance of the things that you already have and the problems that you already have. Because they're also the people who are going to notice something weird happens and tell you about outbreak or something odd.
And there are these core things which is really about people noticing when infectious diseases are occurring and affecting populations. And also knowing who to talk to about that and where they can go to and the links that you need between sort of the animal sector and the human sector are only built up by people working together over time. If people have worked together for a long time to try and control an endemic disease when something new happens they'll know who to talk to you. So we kind of argue this case.
It'll take a long time for us to figure out if this works in practice and it's not a trivial undertaking. We kind of think it makes sense. And also a system is more likely to be sustainable if you get results through doing the conservant and control of the endemic diseases that you have rather than not knowing what's going to happen when something new happens. I suppose that's focusing on a few diseases and different diseases as well.
Because the virus is in our need viruses. Have I was just... Oh, we're getting into the technical... It is, yes.
And also getting into the bacterial... Imagine there's trying to get a good idea of all the different possible types of patterns. And we haven't really mentioned some of the other diseases that can be caused by... I imagine nematodes and all these sort of things which there's a lot of disease out there.
And it's very difficult to try and monitor everything. But it sounds like you're both getting a good try at trying to consult the bonds that we've put links to both the papers on the blog. So if anyone's been listening and interested in reading a little bit more about that you can download the papers through the links that we'll get. And with that, we'll bring this week's podcast to a close.
Finally saying thanks again to Sunning to Joe for talking to us about this really interesting topic. And hopefully tuning in next time and listening to Naturally Speaking. And hopefully it won't be as long as we have to. No.
Oh, no, no. Thanks for listening to the Naturally Speaking Podcast. If you've got any ideas for future shows or want to get involved, please contact us. We'd love to hear from you.
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