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Features: Faculty Insights


In February 2020 Julia Gog, Professor of Mathematical Biology at the Department of Applied Mathematics and Theoretical Physics (DAMTP), was released from her normal duties to devote herself entirely to the fight against COVID-19. In this interview she tells us about her journey through the pandemic so far.

What kind of work did you do before the pandemic struck?

Gog: My research area is the mathematics of infectious disease, particularly influenza. For example, we have worked on the spatial dynamics of the 2009 swine flu pandemic, particularly in the US. Another example is the BBC pandemic project. This involved making a documentary, called Contagion! The BBC Four pandemic, but at the same time conducting a huge citizen science experiment. We were collecting data to understand better how people move and mix in the UK in current times. The point of that was to help us make better-parameterised models for pandemic spread for some hypothetical pandemic, hopefully in the long distance future — that's what we were hoping then.

When the pandemic started, how did you become involved with the fight against it?

"The personal experience and the population experience are weirdly tied up in this job and in this crisis. A uniquely strange experience!" Julia Gog

Gog: Actually before the pandemic hit, after the BBC project, our work on these large pandemic models was picked up by a group called SPI-M, which fits into the Department of Health and looks at pandemic modelling. I was asked to join SPI-M and initially hesitated because I thought of myself as a backroom theoretician. I make models and look at things years after they happen to try and say if there's something more about pandemics we should understand. I didn't think of myself as someone who'd get involved in a real-time response, and SPI-M was all about gearing up for having the modelling groups at the ready in the case of a pandemic.

So initially I said no. But then the current Chair of SPI-M, Graham Medley, approached me and said, "Well Julia, if there was a pandemic wouldn't you actually want to be involved in helping?". I thought, "Oh hang on, you're right," and so I joined SPI-M. Outside of a pandemic this was not a big commitment, it was just meeting occasionally, looking at what models are available and thinking about what seemed like a side issue then, but is of course an absolute core issue now: what data flows would we need in order to be able to answer the questions that will be asked in a hypothetical pandemic in the future. Then of course it all changed.

When the pandemic hit, were things as you would have expected from your work on SPI-M?

Gog: Certainly for me it was utterly different to how I imagined things would be. I don't think I'd really thought through the detail of what it would be like day to day, trying to keep tabs on a pandemic. I don't think anyone really thought about testing. COVID-19 is not a disease like, say, measles, where someone really knows they've got it. With COVID-19 a lot of people are asymptomatic, and there are other diseases which look like COVID-19, so you've got to have testing. But testing capacity was extremely limited to start with. And now we've got other problems, some types of tests have imperfect sensitivity. So even understanding surveillance of the current situation has been surprisingly complex.

How do you fit into the effort to fight the pandemic now?

Gog: As an emergency kicks off the Scientific Advisory Group for Emergencies (SAGE) is initiated, and pretty early on I was called in to participate in SAGE.

I wasn't running one of the main pandemic models, that was never something I was going to do, but I kept finding places where I could see I could do something. Particularly early on, it was some of the schools work, looking at what we know about closing schools. What can we extrapolate from 'flu to tell us about what would happen with COVID? We'd guessed already at that time that closing schools would do immense harm to children, and now the evidence for that is much clearer.

Then of course I was working on the next question, asking if we can reopen schools. So schools became a topic I could see I could do something for, pulling together evidence and running very simple models. Drawing together and synthesising things became a niche where I could see that I could fit in and do something useful.

What is it like participating in SAGE?

Gog: It's interesting because all I had seen up to then was what happens on SPI-M, where asks come in from SAGE. There are weekly routine questions like "what is the estimate of R or growth rate in different parts of the UK", for example. Then there are specific questions, for example "what would be the effect of closing schools or of reopening them?" Sort of homework questions, if you like.

When I got to see what SAGE was doing I could see a little bit more of where those questions were coming from. SAGE pulls together the scientific expertise, not just from modellers, but from other scientific disciplines. A simple way of seeing is it that SAGE is giving input and advice so that our Chief Scientific Advisor and our Chief Medical Officers have the best evidence at their fingertips.

At first, even attending SAGE was absolutely terrifying. I remember being a bit stunned by so many things flying past quickly from different dimensions. Things that you don't think about as a modeller, for example operational issues concerning the current state of testing or the NHS.

One thing that stayed with me throughout, and is definitely going to shape my research in future, is the other SPI group, called SPI-B where the B stands for "behavioural science". I suddenly realised that maybe our modelling is not so different to what they're doing, trying to translate very complex pictures and extracting the key thing. Working with the researchers on SPI-B has been an absolute eye-opener and I really hope those collaborations are going to persist long past this pandemic.

Can you give an example of how behavioural science links to your work?

Gog: A key thing that comes up repeatedly here is adherence. In modelling we can't just assume people do what they should do; that they stay at home in lockdown or tell the truth to Test and Trace. We've got to try and actually model the reality of what is happening. Understanding this is straight behavioural science. For example, when it comes to reporting contacts to Test and Trace, it's not just that people lie or people forget, it's not as simple as that. If you report someone and it's one of your friends who are only going to earn money if they're in work, then are you going to do it?

With the modelling, you've always got to look at sensitivity to adherence. What if people change their behaviour in an unintended way in response to a change in the rules? Does it vastly overwhelm any benefits of this change? If so, go and think again. Modelling wise, I'm not going to even try and predict exactly what people do, but what I have gained is an awareness that it's complicated. So I'll have to have a variable in there representing changing adherence, say, to show whether the main results would be robust to changes here.

How did you combine your day job as a Professor at DAMTP and Fellow of Queens' College with your work on the pandemic?

Gog: Come February last year I realised that something very big was happening. I remember I'd gone to dinner with a few colleagues and was talking through some of the stuff I was doing for SPI-M for the next week, and that I had to go back that night and finish my marking pile for my supervision the next day. All of my colleagues there were amazing, they more or less shook me by the shoulder and said "stop, Julia, just engage brain for a moment. Don't you think that someone else could cover your supervisions?" I'm so lucky to have colleagues that would do that.

Then Department of Health and Social Care wrote a letter asking for me to be seconded full-time in light of COVID-19. Queens' College and DAMTP released me immediately.

You also co-founded the JUNIPER modelling consortium, which comprises academics from seven universities who have joined forces to address pressing questions about the control of COVID-19. Please tell us more!

Gog: The initial pressure was that we needed funding to make sure we're underwritten to continue our government work. But then we realised that all the different research groups that are part of JUNIPER were repeating some of the same work. For example when we get new types of data we have to unpack it to explore what's there. We can just pool our resources there and do that one together. Then we could see more and more topics that might be more natural to work on together.

Also with JUNIPER we can be more academically focused and forward-looking. With SPI-M we tend to be reactive, but as academic modellers we can scan the horizon for topics that are going to be really important in three or four months from now, that we're going to have to start work on now. I can already see how brilliantly JUNIPER researchers are working together, how many collaborations are emerging, and what a supportive group it is. What we are doing is turbocharged.

[You can find out more about some of the work that is being done by JUNIPER members — from understanding vaccination to exploring the reopening of schools and universities — on Plus magazine.]

Do you feel that, on the whole, the results of your work are taken on board?

Gog: That's a hard one to answer because I wouldn't want the work of modellers to be considered in isolation for policy decisions. The questions we are asked are not in the form of "should we open schools or not?" That's not what we're asked because we shouldn't be asked that. We're asked things like "what will happen if we open schools?" This is a different question because there have to be so many other things weighed up. For example the harms that happen to children if they're kept at home, as opposed to getting on with their education and lives at school. It's not for us to balance these factors.

We can we see a glimmer of light now with R clearly below 1 and negative growth rates. That's fantastic, we can open something. But only something, not everything. Choosing what to open should never be down to a mathematical modeller. These are complex ethical and social judgments, taking into account all kinds of factors.

Is there anything about your work on COVID-19 that stands out in a positive way?

Gog: The whole thing is pretty dark and of course none of us wanted this to happen. But for me the number one positive is the people I've met and have been working with: from other scientific disciplines, for example the behavioural scientists, but also other modellers. I have known many of the senior modellers in JUNIPER for a long time, and several of us have overlapped in research groups in the past. Now we do that again (at least virtually) and it's an absolute joy.

The other group that I've really enjoyed working closely with are the civil servants, particularly within the Department of Health and Social Care there's the squad looking after SPI-M. To be honest, I knew nothing at all about how government works before this started. To understand how we as academics can interface with government and do something useful required the civil servants to steer us through.

But that goes both ways because it becomes clear sometimes that they have little idea how universities and academics work. It's quite an odd relationship because we are fully independent: we can literally say "I don't want to do that" and walk away, and there is no come-back. For the civil servants it must be worse than herding cats! And for us it's throwing things into a mystery black box. The independent academics and the civil servants work to try and find the intersection between what's valuable and useful for government policy decisions and what's actually doable by us, and making sure it happens in a timely fashion.

How would you summarise your experience over the last year?

Gog: We are very much part of what's happening to everyone in the country at the same time as being scientists involved in the response to what is happening. Some of us have been ill ourselves with COVID, some of us have had family members being ill, we've all been hit by restrictions and tiers and lockdowns. So it's really odd when you're sitting there talking about a lockdown and you're struggling because you're affected yourself by the same lockdown. The personal experience and the population experience are weirdly tied up in this job and in this crisis. A uniquely strange experience!

This is an abridged version of an interview conducted in February 2021. You can listen to the full interview in this podcast on Plus magazine.

Photo: Julia Gog and the cat Finn. Credit: Lionel D’souza