Illustration showing three z's to represent sleep, a sun, a kg weight and a carrot.

Opinion: The science of staying well

Are we stuck with the immune systems that we’re born with or are there nutritional and lifestyle choices that we can make to optimise and maintain a healthy balanced system? Immunologist Dr Jenna Macciochi looks at the science of staying well.

Portrait of Dr Jenna Macciochi


It’s a simple fact that our immune system is shaped by things that we can control, such as diet and lifestyle, and things we cannot, such as genetics, socio-economic status and previous infections. It’s important to keep that in mind when thinking about optimising immune function. However, there are daily actions we can take that will help to maintain good health and wellbeing.

Sticking to a healthy balanced dietary pattern, such as the Mediterranean diet (whole grains, fruits, vegetables, seafood, beans and nuts), rather than hyper-focusing on specific superfoods is a good place to start. As is getting regular movement into your day, including breaking up sedentary periods at the desk and maintaining muscle mass through several resistance based workouts per week. Keeping a consistent sleep pattern, spending time in nature, managing unwanted stress and focusing on your gut health are also beneficial and relatively easy to achieve.

Diet can impact immune function in several ways: being deficient in any of the essential nutrients can lead to an immune deficiency. Food provides energy to fuel your immune system, which is a very energetically costly system, especially when running a fever for example. Food is also a form of building blocks for the immune system, as well as our signalling molecules, and provides a source of antioxidants and anti-inflammatory molecules. 

Sticking to a healthy balanced dietary pattern, such as the Mediterranean diet (whole grains, fruits, vegetables, seafood, beans and nuts), rather than hyper-focusing on specific superfoods is a good place to start.”

Can our immune systems be trained or re-educated? It depends. The immune system can be trained and educated by a vaccine, whereby it develops a memory of that exposure which protects in the future. The same principle applies to exposure to some germs. For example, contracting chicken pox often (but not always) results in a lifelong immune memory that prevents a person from becoming infected again. However, such a robust memory response doesn’t occur for all infections, including the highly contagious norovirus.

And then there’s the key role played by genetics. It’s hard to disentangle the exact contribution because genetic expression is also linked to diet, environmental and lifestyle factors. And the contribution of a specific gene varies from gene to gene. Some genetic variants will almost certainly lead to a specific immune trait but, in most cases, it’s a mix of many genes that result in a particular trait.

Autoimmune diseases, for example, are caused by a complex mix of genetics (usually
multiple different genes) combined with various environmental factors that results in a breakdown of immune tolerance (a tolerance to our own proteins). This results in an inappropriate immune response to a part of our body.

Often this can start years before symptoms appear, and we now know there is a key role for the gut microbiome in educating and training our immune system to prevent autoimmune disease. 

There is no single method to develop a strong or weak immune system, but some studies show that certain medications can impact immune function. Vaccines help us develop an immune memory to a specific germ, the goal of this is for lifelong memory but the duration of the memory will vary from germ to germ and vaccine to vaccine.

So, when it comes to staying well, the adage ‘everything in moderation’ really is the best way forward.

You can also listen to Dr Jenna Macciochi speak with other Sussex experts on Covid-19 here:

Ask the Experts - Discussion on COVID-19

  • Video transcript

    Ask the Experts: A discussion on Covid Transcript

    [Visiting Professor and BBC presenter Claudia Hammond] Hello, everybody. I am Claudia Hammond and I am delighted to be here to host Ask the Experts live for Sussex University. Because I was an undergraduate at Sussex studying Psychology quite a long time ago now. And I am now back there for some of the time being a visiting professor of the Public Understanding of Psychology. I present All in the Mind which is BBC Radio 4 Psychology and Mental Health show and podcast. But I also cover Global Health as the presenter of Health Check and The Evidence which are both on BBC World Service. Now, on January the 8th, last year on Health Check, the programme I present, we covered a new mysterious virus affecting some people in China. Little did I know that now, more than a year on I would've made it, I think it's 82 programs about it. It might be 83. If I can't sleep at night I try and work it out going right back to January 8th and I never quite get in the end so it must work. But yeah, it's a lot. So the amount that we do know about it, since that first discussion I remember having on January 8th last year, about this mystery disease, is really astonishing how much is being learned in this time. And this is a chance for you to hear more about some of the work that's been going on at Sussex and to put your questions to our really excellent panel. And this panel that we have chosen will give you just a sample of the expertise working on the pandemic at Sussex. There's all sorts of other research going on too including, for example, the impact of the virus on gender equality, and on LGBTQ communities.

    Now, this is the first event in the Ask the Experts series which brings together a panel of world-leading experts in their field. So, thank you so much to the panel who've all made time tonight, and thank you to all of you for joining us, watching, and thank you to everyone as well who've all supported the University’s COVID emergency appeal in support of students in hardship. So, over the course of the past 12 months, we've seen the number of students applying for hardship bursaries or needing mental health support, rise significantly, maybe not surprisingly and the generosity of the alumni community has been hugely appreciated, so thank you for that.

    So, what's going to happen this evening, is that I am going to introduce each of our four panellists in turn, for them to talk about how their work relates to the pandemic and what they have discovered so far. Then we'll turn to your questions and so do be putting your questions into the chat whenever you think of them, even though we'll come to those later. Because I want to leave half the time that we have for those. And a lot of very organised people have sent them in, in advance, so we have all sorts of good questions, and I am fascinated to hear the answers to some of those. But before all that, we thought we'd do a quick poll on COVID vaccines. So, the question is, you should see this come up, is, do you want to have a COVID-19 vaccination? And the possible answers there are yes, which also counts if you already had it, no, or you're not sure yet. So, do be clicking on those now. And it could be very interesting to see what it is people say. Now, while you do that, let me say hello to Professor John Drury. He is well-known for his work on crowds and how groups behave. He is a Professor of Social Psychology at Sussex. And he's also a participant in the... or as I think is an excitingly named, SPI-B advisory subgroup of SAGE. And he's a member of Independent SAGE and of two British Psychological Society COVID-19 task force working groups because there has been a huge amount of work that started very quickly within Psychology, so he's been very much steeped in this. Hello John, how are you?

    [Professor John Drury] Yeah fine, thanks Claudia, how are you?

    [Claudia Hammond] I'm good, thank you. Now, I wonder if while people are voting, honestly we don't want to skew that vote, but I wonder if you dare hazard a guess as to the polling answer?

    [John Drury] Well, that's a good question. I think it really depends on who our audience is because vaccine-hesitancy in the UK is actually pretty low. We hear about vaccine-hesitancy and it varies a lot around the world. We know in the general, it's very high. So, I would say if we got a very British audience then most people are going to say yes.

    [Claudia Hammond] Well, let's have a look, we have the results now. Let's have a look, and see what they are. Oh yes, you were right there, so 93% of people want to have a COVID vaccination, 3% don't, and 4% aren't sure yet. Gosh, that is a very interesting and overwhelming number there. And of course, it is an audience who decided to come to watch this as well. So, John, you work on group behaviour, can you tell us about what you've been working on when it comes to the pandemic?

    [John Drury] Yes, well much of my work over the last 15 years, has been on public behaviour in emergencies and disasters. And because of that, from March last year, I was asked to be part of one of these scientific advisory groups for the government as Claudia mentions, SPI-B. And one of the main things we do is look at public adherence and we try to give advice on what would help people adhere to the behavioural regulations like staying at home, distancing, wearing a mask, and so on. And within that, I've kept a careful eye on the data. I mean there are regular surveys, regular behavioural reports on the extent to which the public are adhering with the regulations. But, one of the things I've learned is that it's not only psychology. Psychology has a place, but a lot of the reason why people do or do not adhere to some of the required behaviours is practical. It's material, and my current research project, or one of my current research projects, is looking at mutual-aid groups, the COVID mutual aid groups that have sprung up. If you remember, they got a lot of publicity about a year ago. We don't hear so much about them now; they're still around, and the reason that's relevant to this is that they help people who have to self-isolate. If you think of the difference, between wearing a mask, washing your hands, keeping 2 meters apart, and having to stay at home for 10 days because you've got the infection or you've been in contact with somebody else, the big difference is you can wear a mask, distance, under your own steam, You can do that by yourself. But you can't really very well isolate without the support of others. Material support, and financial support is also really important. So, I think that's one lesson I would take from the pandemic, is the role of the structural, practical resources that make some of these behaviours, that makes psychology relevant. And we hear, we tend to hear quite a lot about people breaking the rules, and we've heard quite a lot of people may be being tempted to be, you know, judgemental about other people breaking the rules. Is that a mistake to do that? Do more people actually obey the rules than we think? Well, it actually depends on which behaviour. we're talking about. I mean if we stick with some of the most visible behaviours; staying home, wearing a mask, distancing, most of the evidence across different sources, whether its self-report, behavioural suggests that adherence has been high most of the time through the pandemic. And there were certain periods, over the course of the last year, where adherences dipped a little, it tends to go up at periods of lockdown periods, and periods when the infection rate's very high, because people respond to the threat. We might talk later about why it's low with some behaviours, because even with self-isolation - it's not high enough. But all of the others, I think most of the people I know in the advisory groups will say that public adherence has been very good, and good enough. Just to take some recent evidence, we know how quickly infection rates have been coming down since this current lockdown. This current lockdown even though it's not as strict as the first one, has worked. And that is public behaviour.

    [Claudia Hammond] And that's interesting because you sometimes hear people, particularly with this current lockdown, say how it's not the same as before, look how many people are out and about.

    [John Drury] Well, it's true. It's true, it's not as strict. You've got 50% of people still going to work, that's too many. The Government made a political decision not to be as strict as last time. And you know, you could then argue that infection rates and death rates would've come down even quicker. And with the people that others saw on the street, and were critical of these are people who were mostly acting within the rules because rules allowed them to go into work and so on. That is a major difference because, of course, contact is not the same as adherence. You could have contact, we could still be adhering to the rules.

    [Claudia Hammond] Well we'll talk some more about behaviour later on. So, thank you very much for the moment, John. Now, one of the words that has, I think, never been discussed so much in public life and on the news and so on, as in the last year, is immunity. And we're very lucky to have Dr. Jenna Macciochi, who’s a lecturer in immunology at Sussex. And also, author of a book called, Immunity: The Science of Staying Well. Welcome, Jenna.

    [Dr. Jenna Macciochi] Thank you, Claudia. Thanks for having me. So, could you tell us a bit about what you've been working on over the last year? Yes, so my background's in immunology. And I am very passionate about the subject area. And I’m also passionate about the communication of science and the proper way that we can really convey evidence-based messages and think in a way that is accessible to the public. So, for the past year, I've worked with the Comms. team here in Sussex, and numerous other media outlets to help break down some of the scientific literature that's been coming out at an incredible rate over the last year. And using various social media channels as well to kind of dispel myths and get a dialogue with the public where they can break down that barrier between academics and the science, because I think it can often feel like there's a bit of a disconnect there.

    [Claudia Hammond] Within the last year, how much would you say has been learned about immunity and this particular virus?

    [Jenna Macciochi] It's been incredible. I mean, it's just being fantastic to watch the whole field evolve. We've really pushed the boundaries of what we know and understand about the immune system. You know, the question of how long does immunity last? It's got everybody in the immunology field scratching their heads, seeing this is the question that we've been trying to understand for a long time. What's the specific ingredients we need to get long-lasting durable memory responses from our immune system? Why do some infections do this and some don't? So, I think it's really kind of shown, immunologists have shown up and been like "yes, we're here, we're working collaboratively all over the globe to piece together the jigsaw puzzle" and also acknowledging there's huge gaps in our knowledge, and immunology as a field. We need to encourage new scientists to come in and start working on that.

    [Claudia Hammond] Do we know the answer now or how much do we know of the answer? How long does immunity last if you've had COVID-19?

    [Jenna Macciochi] I mean I think that the real answer lies in the time that you have to measure it. So, the longer we are from those people who were infected at the early stages of the pandemic, the longer we can measure. And there's different aspects of the immune system that we can measure as well. And now, with the vaccination roll-out, it gives us another opportunity to follow people and look at how long and how durable that memory response is.

    [Claudia Hammond] Yeah, I think it's interesting, the different sorts of immunity, because there's been ever such a lot of talk about antibodies and whether people have antibodies or not. But there is also other types of immunity. There's a type of immunity called T-cell immunity, which there doesn't seem to be nearly so much talked about, and that may last longer. Is that because it's harder to measure, so it's harder to do those studies?

    [Jenna Macciochi] Yeah, exactly right. Antibodies are fairly easy to measure in blood, so it's a correlate of protection, it's something that we can use to correlate that the immune response has occurred. But we also want to know what the T-cells are doing. And within the T-cells, there's different subsets that may be doing different things. So, you can only really get a comprehensive picture, if you do lots of, involved technical analysis that would require a lot of labs and other resources. So, antibodies are sort of the easiest way but it doesn't give you really comprehensive measure.

    [Claudia Hammond] And so, when you hear a study will say, they've studied people for say, five months or six months. And that a certain proportion do still seem to have immunity in that time and that they still seem to have the antibodies. That doesn't mean it only last six months, does it? It means they followed them for six months and they still had it?

    [Jenna Macciochi] Yes, exactly and sadly, we can only measure with the time that we have since the pandemic began.

    [Claudia Hammond] So, what is your hunch, if you like about how long immunity might last?

    [Jenna Macciochi] I think with respiratory viruses is in general, you don't get such a durable immune response, so you might be looking at a couple of years. And we can also look at the other related Coronaviruses from the SARS 1 and the MERS pandemic, epidemic, from several years ago, and I think those people that were followed it was also a couple of years. But you will get a lot of variation within a population. I think with vaccination you might have a little bit more control over that, and you might get slightly more consistency in the response.

    [Claudia Hammond] Well, we will hear some more from you later on as well. So, thank you so much for the moment, Jenna. Now, one profession that has been very much in the public eye, and has never been on the media so much, are virologists. And we have Dr. Ed Wright, again from Sussex. He's a senior lecturer in Microbiology. Ed, hello, how are you?

    [Dr. Ed Wright] Hi, Claudia. Good, thank you very much.

    [Claudia Hammond] Good, so could you tell us a bit about what your work has involved over the last year?

    [Ed Wright] Certainly, so, I've got an interest that's been part of my research for fifteen or so years. Looking at emerging viruses and these are viruses that as the name suggests, we weren't aware of, and all of the sudden, they've either appeared in animal populations causing disease or transmitted into humans. And there are three main aspects that I'm most interested in when studying these viruses. What is the original host for these viruses, where do they come from, where do they circulate? When you're thinking about emerging viruses, a lot of people may start pointing the finger at the bats, and we're starting now to know a lot of information about how bats are able to carry these viruses and they allow them to spill over from those animals into other animals or direct into humans. And this is why we undertake studies in bats. We work with collaborators around the world and screen the samples from animals for the presence from the antibodies that Jenna was just talking about to these viruses, in able to build up a picture of where certain emerging viruses are circulating and what threat they pose to that local population. More recently, starting in 2014, 2015, I've been interested in developing vaccines to try and limit the impact that these viruses have in humans and also animal populations that can become infected. And this started, as I said, in 2014 or 2015, during the big outbreak of Ebola that was in West Africa and we've continued that on looking at other viruses that cause haemorrhagic fever disease, such as the Lassa fever virus. And we're turning the technology that we developed as part of that study, to target SARS-Coronavirus 2 that causes COVID-19. And we hope to have a vaccine candidate that's been developed through the spin-out company established with an initial study, entering clinical study soon. But the third arm that we're interested in when it comes to emerging viruses is what tissues do these viruses infect. It's specials assays that we can do to generate virus particles that to a cell, to do one of these antibodies that we've been talking about. It will look to those components, it's like a real virus but it's not harmful, it won't cause any disease. And that really allows us to do more studies in the laboratories that we have here in the local Kent laboratories. As I'm sure a lot of the audience is aware, some of these emerging viruses, or the majority of them, are highly pathogenic which means the disease they cause is very deadly and so to work on the actual virus, you need to do that in laboratories that have the appropriate containment built into them and that is quite restrictive and there are only very few of those available. So, with our virus-like particles, we're able to do a lot of work. Talking about look at what tissues is infected, and this is actually something we're doing in collaboration with one of your colleagues in the Department of Psychology, Catherine Hall. Now we're looking at specific tissues within the airway which coronavirus will infect. And that's our response where we'll be involving the vaccine development, vaccine and evaluation, in tissue tropism; what cells the virus will infect and regard the coronavirus. But, we have a long history looking at other viruses, rabies, Ebola. I could go on but, I think in the interest of time, I wont.

    [Claudia Hammond] And I'm intrigued that you were working with a psychologist on which tissues were infected. Why work with a psychologist on that?

    [Ed Wright] Because they have an interest in certain neurological developmental processes. And so, they have the required expertise and facilities to undertake the experiments that we needed to do. And so, we were able to pair up and take funding from the Medical Research Council in the UK. We started that project in December last year and it's very exciting; hopefully generates some meaningful results. And have an impact over the coming few months.

    [Claudia Hammond] And with the vaccine that you're working on since we do already now have, you know, several different successful vaccines. What is different about your one and why continue to do that research to find another? Or will we always need new ones?

    [Ed Wright] Very good questions. I'll try to be concise. the vaccines that we have at the moment are very highly, highly effective against stopping hospitalisation, death from Coronavirus / SARS-COV 2. The effectiveness against the upcoming variants has been questioned. It's still being shown from the data we know so far, to be highly effective, again in stopping hospitalisation and death. But at some point there may be variants which it isn't confirmed protection against by these vaccines. And there are other Coronaviruses that Jenna mentions, SARS 1, MERS, and there are seasonal Coronaviruses that circulate every year within the population. And so our technology allows us, what we established, as with Ebola, the different types of Ebola, to develop a vaccine that will provide protection for ideally - and the initial data is looking promising - provides protection against a broad range of different types of Ebola virus, or different Coronaviruses. So, you won't have to worry about the emergence of variants or a new species of Coronavirus.

    [Claudia Hammond] So, the idea is that you can keep using the same vaccine without even having to tweak yet because it already works in a different way and so covers a lot of variants, even the variants yet to develop? Which would be amazing, wouldn't it?

    [Ed Wright] That is our aim, yes. Yeah, well very good luck with that. We all hope you'll succeed at that. So, thank you very much for the moment to Ed there. And our fourth guest on the panel is Dr. Joshua Moon who is a research fellow at the University of Sussex Business School in the Science Policy Research Unit. Now, he's an expert on global health emergencies and a member of a global research study into international COVID-19 testing systems. Welcome, Joshua.

    [Dr. Joshua Moon] Hi, Claudia.

    [Claudia Hammond] Hello, hi. So, can you tell us a bit about what you've been working on in the last year?

    [Joshua Moon] So, right back to the start of my career, my initial PhD. was on how we learn from academics and how we actually respond to global health emergencies like pandemics, like COVID-19. What my expertise really focusses in on is what we know about how to respond to these types of events. And how we know it, but more importantly, what we do when we don't understand something about either the virus, or the contacts in which an infection is spreading. One of the key things that's been clearly happening throughout this pandemic is that we've been increasing our knowledge and we've been learning more and more about the virus, as we move forward. And so, beginning in June last year, we started a project and look more specifically at how different countries are setting up their testing systems. Now, that being not just what tests are they using, whether it be the PCR test, that has kind of risen to dominance as a gold standard for a diagnosis. But also how those tests are actually used. How they are incorporated into the contract tracing system. How the contract tracing system tells people whether or not they need to isolate. And how that isolation is then supported. And we've been studying this across different countries, to try and learn what different countries are doing and how well different countries are actually implementing their testing responses. And that research is now continuing, we've expanded our team so we've increased from 6 countries to 8 countries that we're comparing across. And we're now looking further ahead and to not just thinking about what the PCR test is doing, and how that's been implemented and put together. But also, how antibody testing- antigen testing - the mass testing that's happening now for teachers and pupils, for the UK opening schools. Across a wide range of different countries, as well as looking even further to the future for how some lessons of the COVID-19 can help us with future either pathogen threats, future pandemics, even things like can anti-microbial resistance.

    [Claudia Hammond] And, is it a case that studies like yours that are comparing what's going on between different countries are quite unusual because as you say everyone is doing differently. And so, it would seem to be good if we learn from that. But, I sometimes wonder whether we look enough at that and whether we do. So even at the moment, say within the UK, I think in Wales, four people can meet up outside. In England, two people can meet up outside. Are we ever going to know, which of those was right, in a way?

    [Joshua Moon] To an extent, I don't think we ever will know which was the best. Primarily because all of this depends on contacts, it depends on local culture, it depends on the actual demographic make-up, who is doing what. As John was saying, depends on individuals and support factors. And which way is 'The Best' is probably never known. But, these kinds of international studies really give us an insight into which individual policies are having an impact. And so, allowing us to understand not only that supporting people in isolation works but what kind of supports. Some of the evidence that we've been finding is that actually direct support, being the kind of South Korean deliveries of medicines and food direct to people's doors. Are actually much more supportive than the kinds of UK-European view, which is very much that you expect familial support or community support and provide just a kind of standard sick pay support, or even furlough.

    [Claudia Hammond] And so in your study, where you've looked how different countries do you testing? And I think you said you looked today 8 different countries. Is there one that stands out for doing it better or more comprehensively? Or even targeted in the best way possible?

    [Joshua Moon] Strangely, it's changed. As the pandemic has gone on, we've seen different countries kind of rising and falling and changing the way in which they're responding. So, in the first wave, we very much saw Germany and South Korea coming out strong, coming in with really well-developed testing system. But over time, we've seen other countries like Ireland catching up. And we are only just now starting to also look at Australia and Canada and how their systems compare. Because our original 6 countries were very much located in either in Europe with one or two outliers. And so, we're really trying to bring in this global perspective now. So, the results of that, we'll have to wait and see.

    [Claudia Hammond] Yeah, it would be really interesting to see what happens there. Well, thank you for the moment, and we have lots and lots of questions coming in. Do put questions into the chat that you'd like to ask any of our panellists. But thank you, Joshua, for the moment. So, our first set of questions we're going to look at, are on vaccines, and not surprisingly lots of questions are being sent in on vaccines. Jenna, I wonder if I could put this one to you because it's about immunity. Sally says, "I heard the vaccines' side effects more likely in the young and in those who've had COVID because they amount a stronger immune defence to the vaccine. Does an individual's response to the vaccine, and what side effects they get, give any indication as to how severe their COVID might have been if they'd had it before." What is the relationship between the side effects people get and previous COVID."

    [Jenna Macciochi] Yes, side effects are quite normal, so we called this the reactorgenicity of a vaccine and then some people experience normally minor things around the site of the injection, maybe feeling unwell and it's normally very short-lived. And there is the government yellow card scheme to report anything that's a bit more extreme. And then the immunogenicity of the vaccine is how well it works, so that's looking at things like that antibody response that all start to be seen in the weeks after the vaccination. So, it takes a bit of time for that to get going, and yes, we're starting to now, really I think put this under the microscope a bit more than we ever have before. And there is not any strong evidence that not responding with any side effects doesn't necessarily mean you're not getting an immune response. So, it doesn't just indicate that your body hasn't responded if you just had nothing, you know, and your friends has had all the headache and chills and pain and fever. But it does seem to be that, younger people, women, and people who'd have COVID previously seem to respond more, and have experienced more side effects. And the symptoms you get from a side effect from a vaccine, or when you get sick, this is normally the result of what your immune system is doing. So, it is a sign that there's an activity with the immune system going on.

    [Claudia Hammond] Thank you for that. And Ed, here's a question that I think you might be able to answer. Again on vaccines: Is that one vaccine that is better than another? And what about the idea of combining one dose of one vaccine and a second dose of another one.

    [Ed Wright] So, depends on what you mean by better. If we're talking about distribution globally, then I'm sure everyone's aware that certain vaccines are able to be transported at lower temp - it's easier to get to areas where they may not be able to maintain that ultra-low temperatures. If you're talking about the new responses, I might confer that one over to Jenna. If you are looking at protection provided against hospitalisation or against deaths, all of the vaccines that have been approved, certainly within the UK, have a 100% protection against hospitalisation and death and so, they are equally matched in that regard and I'll leave immune responses over to Jenna.

    [Claudia Hammond] Yes, Jenna. What do we know about immune responses?

    [Jenna Macciochi] I think it's you know. Often when I'm teaching the students I say there's more to a successful vaccine than just the immune response. It's also about, like I said, giving it to the people who need it. And how easily it can be delivered and stored, and the whole manufacturing process. But I think, as I've said, they're all equally protecting from severe diseases as what we've seen in the approved vaccines by the UK anyway. Protecting from hospitalisation but there's very minor differences in protection between them. And I think that the best vaccine is the one that you have accessibility to really.

    [Claudia Hammond] And we've got a couple of questions about transmission. Phoebe would like to know, she says, "she heard one virologist on TV saying, it was unlikely that somebody who'd been vaccinated could transmit COVID-19 to another person, but then heard the opposite in a briefing and somebody else – Julia – says "if you can still transmit the virus after vaccination, how is that possible? And is it true after every different type of vaccine, are there differences between them?" And every week, it seems like last week and two weeks before that, there was new research coming out about transmission. What do we know so far Ed?

    [Ed Wright] So, the various studies that have come out in the last week, or not even in the last day, showing that the transmission from people getting a clearer picture of what's happening. I think it's important to set the scene to begin with that there's no vaccine that is going to 100% protect against infection. We get vaccines, such as the best ones; the MMR; the Measles vaccine, the Rabies vaccine, Human Papilloma - HPV vaccine that would confer protection from infection in the high 90's. But no vaccine that's been developed so far will stop someone from getting, becoming infected. Now, once infected, how readily transmissible that virus is, how easily it's transmitted from person to person. It is still something that we're trying to take apart and get to grips with. There was a study that came out, both on the Pfizer vaccine and the AstraZeneca vaccine, that suggests that reduction in people who become asymptomatically infected, who have received one dose of the vaccine, is reduced by about two-thirds. And so, these are the people who aren't going to know they've had it. And so, if you can reduce that number by about two-thirds, then hopefully that will impact and limit the transmission. But obviously, you still have a third of that group, who will be infected and will have the virus. And so, still unclear exactly about how ultimately the vaccine will...

    [Claudia Hammond] But to cut it by two-thirds - that's very good news, isn't it?

    [Ed Wright] It is absolutely, but it is still doesn't mean that we will necessarily be able to do away with all the other counter measure; the distancing, the handwashing, and the face coverings but yes, absolutely. If we can cut it by two-thirds that's a huge help in controlling the outbreak.

    [Claudia Hammond] Yeah. And Jenna, this is a question that funnily enough a lot of people been asking about on the programmes that I do on the World Service, which is "When we will be more information on the safety and efficacy of the vaccine for pregnant women" because they weren't in the original trials. Now, it is the case isn't it, that a trial did just start last week or the week before. That is the first time including pregnant women. But, what do we know in the meantime? Because it is risky if you're pregnant to get the disease as well, isn't it?

    [Jenna Macciochi] Yeah, I think, it's naturally a difficult time for people who are pregnant or considering being pregnant and even breastfeeding. I've heard a lot of questions from people around that. And there is a lack of data, surrounding reproductive health and the currently approved vaccines in the UK. And I think that's because, as you said, the original trials were set up to look at the safety and efficacy of these vaccines in the healthy population, so it's normal that we exclude pregnant people in those early trials. The good thing is that the, speaking from the UK, the approved vaccines are non-live vaccines. And these are traditionally considered safe for pregnant women. But because data is limited, I know for example the UK has stuck to giving cautionary advice. So, it doesn't mean that people should be concerned that these vaccines might cause an issue for pregnant women, it's more being cautious. And I think that we know that vectored vaccines like the AstraZeneca/Oxford vaccine, have been used during pregnancy in Ebola. And so we don't have any red flags that there would be any issues there. And animal studies as well don't show any concerns. But, we do know that people became pregnant during some of the trials, and so far, the placebo people who became pregnant experienced some side effects but not in the people who actually received the vaccine. I think it's going to be a discussion with your health care provider because the Royal College of Obstetrics and Gynaecology in the UK supports giving vaccines to people who are at risk of high exposure, so health care workers for example. And the current advice is to not postpone trying to get pregnant if you have a planned vaccination coming up.

    [Claudia Hammond] Thank you. And one of the things that can be hard is to find good information. And here is an interesting question, Joshua, wondered if you could answer this from Rebecca. "There's a lot of misleading and non-factual information out there about vaccines and all the rest of it. Can you give us any advice on how we tell whether we're reading or watching reliable sources of information?"

    [Joshua Moon] In part, the hardest factor is that most of the information is contradictory and the hardest part is also that a lot of the stuff particularly early in the pandemic, we just don't know. None of the things that get said in many studies are inaccurate and the hard part is just uncertainty. We have this idea that the scientists are infallible and that if a study comes out and says something, that's true, done, leave it. And that's not true. Realistically, one of the best hallmarks of a reliable source, at least for me, is if it comes from a scientist who acknowledges that uncertainty. If it comes from a direct scientific source, that says, "this is what this study had said, this is what we think that means," and couches it in the right terms. Anybody who is coming out and generally saying something absolute of this is a fact and this is exactly what we expect - probably doesn't have that kind of deep knowledge or at the very least has an agenda that they push or who a reason behind them saying it so strongly.

    [Claudia Hammond] Yes, and I guess one of the things people need to do is to look to see what source it's coming from what they're reading. So, often there are things in WhatsApp groups that say you know, my brother's friend, who's a doctor, who knows somebody, who met somebody in the street once, says that "X", which of course is not a source that you know a lot about and so it's a question of looking... I sort of think almost these days, people are required… some of the skills that I use as a health journalist in looking to see whether I believe something, is almost what everyone else needs to do for themselves now. Is to start looking, well what is the source for this, who said it? Is it somewhere else as well and to try to use some of those things? And of course, there are also lots of anecdotes that get told. And actually, there is an interesting question here. Jenna, let me ask you this one. Which is something that has been said and I've heard a lot of this anecdotally in the last few weeks. I'm guessing it's too early for there to have been studies, which is that some people who had symptoms of long COVID, some people, not all, are finding that the vaccines seem to help with the symptoms. Jenna, do you know if there is any evidence if that is something that's happening or it's probably too early for that? Is there a mechanism by which that could happen?

    [Jenna Macciochi] Yeah, I mean, I definitely don't know of any studies that have been designed particularly, to look at this even. I know it's very early days in the long COVID situation because it's a long-term situation, so we need more time. In terms of long COVID, there's a few hypotheses of what could be going on. And my hunch is that is a bit of an umbrella term for a diverse set of situations. It might not be the same in every person. There may be viral reservoirs hanging out that we can't easily test for with a nasals swab. There may be bits of virus that are lingering in the body so that the person's not infectious and again might show negative in the test. but this could be stimulating an ongoing immune response. It may be an ongoing inflammation that's happening in the body even though the infection's resolved, because of some sort of immune deregulation caused by the infection itself. I'm not sure, I mean perhaps if there were viral reservoirs then having the vaccination might help your body get rid of these. So, it's possible and but because we don't know the exact mechanisms of long COVID, it's really impossible to say. But I do think if this is you know, the whisper on the street, then hopefully the people who are studying long COVID are taking those anecdotes, and I think it's really important that we listen to and advocate for people who do have long COVID. I know that people in the chronic fatigue situation have said that we've been saying these for years and then we have long COVID people with similar symptoms and that are really do hope that out of this comes some good where we have proper studies.

    [Claudia Hammond] It would be interesting if long COVID turns out to be as so many people suggest, as you said, a collection of different syndromes. It might be interesting to see whether the vaccine seems to make more difference to some with, some particular sets of symptoms than others then maybe certain syndromes, that would be really interesting. Now we got some questions on behaviour that I would like to put to John and all sorts of different questions here. John, Nick asks "people keep coming to Brighton. What can local councils or the police or the rail companies do to restrain day-trippers from London visiting Brighton and Worthing at the weekends? Now, of course, people aren't supposed to be travelling out of their local area, but, what sort of levers can be pulled?

    [John Drury] Well, the few points to make here, and I think the first one is, there's now a lot of research evidence on what forms of engagement and interaction from police officers and other officials get people to adhere and comply and so on. Lots of research on that And it's about explaining the reasons and so on. It's true, we should acknowledge that it's the being on public transport to come down, that would be the main problem with this example. The newspaper love to have pictures of people on beaches. And now, there's a really good thread on Twitter this evening which said, "We don't know of any study that has used contact tracing data to show that an outside event, being on the beach, has led to an outbreak. It's very visible but it's not really a problem. So, in a way I'd want to say, I get the point about public transport was a bit of a distraction. When we talk about levers we should be focusing on the main areas that we know are where infection is happening, which is, as I mentioned earlier, the workplace, and that is often because regulations are not enforced in workplaces sufficiently. The Health and Safety Executive is being disempowered and many people are not self-isolating when they should. Now, I mentioned this in the beginning, so, I want to unpack that a little now. If we look at predictors, why did people not self-isolate in the UK? Well, there's been lots of research on this. There's a massive survey that's carried out regularly. Lots of studies. One is knowledge. It was knowledge of the symptoms, then knowledge of the rules. So, okay, communication is important. But the other one is financial. People feel the need to out go to work. If you look at who it is, that's not self-isolating sufficiently, it's the poorest people. That is something that will be much cheaper to fix that by giving people enough money than the money we’re spending on privatised test trace. The NHS test and trace. And so, I think, it is a problem for people to be on public transport. but I think it's a bit of detraction to focus on beaches and people strolling about outside.

    [Claudia Hammond] Yeah. I thought it was interesting Jacinda Ardern's response in New Zealand to the case they've had there where a student who was waiting for their test result, didn't isolate and went to, seems to have gone to quite a lot of places, and then that has resulted in a week-long lockdown in Auckland. And I thought it was really interesting that the Prime Minister very specifically said, don't go after this person, we don't want to put people off coming forward. Don't pick on them, which I thought was really, really interesting and possibly not what you might have necessarily seen here with what the papers would've done if there's one person you knew that, which is interesting. And we got a few, couple of behaviour questions for you. This one is interesting. As a manager, I'm wondering what kind of team behaviours I might need to anticipate as we return to work? Between those who've been vaccinated and those who haven't, will there be some fear and anxiety towards those who haven't been vaccinated?

    [John Drury] Well, this is a bit hard to say, because it's a slightly unknown situation. But what we do know, from other kinds of disasters and emergencies is that when people return to normal. There often is a bit of anxiety about going back to normal. But, that doesn't always last. I mean, one of my early studies on public behaviour and disasters was the London bombing of 2005. If you remember these were bombs in the London undergrounds and one of the immediate effects was that people stopped going on the underground. But that didn't last and eventually, they started and it was to go to work, so I can imagine that's possible that you will get a period of people - not everybody - it's going to be quite, is not going to be across the board, it'll be some people more than others who will be hesitant, and slightly nervous, about going back to work and so on, but how long that will last is another matter. I'm not sure.

    [Claudia Hammond] Petra says, do you think that would be riots or unrest if the dates aren't stuck to that have been published. So if pubs don't open in the time suggested. Will people take to the streets?

    [John Drury] Well, I'd to say something else before we talk about that. It's a good question because a lot of my research is on riots and protest. But the whole dates versus data thing, I mean, it's a bit odd isn't it? The Prime Minister says it's going to be about data and not dates. And then he gives us a date. And he focuses on the dates. And having focused on the dates, how is he going to change his mind from that? So, when this all happens, when conflict happens, it's yes, there’s, a wider context of illegitimacy and unfairness. But there's also proximal dynamics which means, how people are being treated at the time, by the police. Okay, so you can have mass protests in street, perhaps, if people aren't allowed to go to the pubs. But whether that turns violent or not, really depends on how that crowd is managed by the police. Because most crowds are not violent, most protests are not violent. It takes quite a lot to turn a protest violent.

    [Claudia Hammond] Well, thank you for those. Joshua, I've got a question for you. This is quite a hard question, but, I'll put it to you anyway and see what you say. "I would like to know", says somebody, "what's the counterfactual death and morbidity toll in the UK might have been if that haven't been any lockdown?" Could this be modelled to work out, what would've happened if we hadn't locked down at all.

    [Joshua Moon] You weren't wrong about that being a hard question. It's a good question, though. I mean, could it be modelled? I would assume it could. The issue with modelling in kind of general is that models of very dependent on their assumptions. And so, there would have to be a very strong assumption about what the impact and effect of each of the different lockdowns was. And then within, that would all sorts of stress testing. But then the secondary question is, would a model like that be useful? There's an old quote by a Mathematician called George Box, which is basically all models are wrong, some models are useful. And that's the key, is that a lot of the modelling that we're seeing has flaws, it has issues, and the assumptions that advantages that they are useful for what we are trying to predict and to help us to make decisions under scientific uncertainty. And the key is that models will not give you the correct answers, but they will give you a guideline as to how to then deal with predicted possible futures. Because there's no one, "yes this is going to happen future". And so models give you those options and the ideas behind those options, and possible futures for how different policy preferences might actually impact the course of the epidemic. And so, realistically, I think the counterfactual would have a lot of flaws but I'm most not sure would be a useful thing to have.

    [Claudia Hammond] Interesting, answer. And Jenna, I know you look at immunity and lifestyle as well, we've had quite a few questions for what people can do to improve their own immunity and to protect themselves, maybe against the virus. Lots of suggestions; eating gluten-free sourdough, eating coconut oil, taking vitamin D supplements, taking milk thistle... What do we know, what can improve your immunity diet-wise and would that work against a virus like this?

    [Jenna Macciochi] Yeah. I mean, I think the one key thing that I would love people to take away is that there was no single, silver, magic bullet and there's no silver magic bullet for boosting your immune system, and even that term is scientifically not only something we could really use for vaccinations. I would encourage people to take a whole 360-approach to their diet and lifestyle. So, just eating one single food or taking one single supplement is not going to suddenly make your immune system worked better than it does in its baseline. But engaging in lots of positive health behaviours around diet and lifestyle, good sleep, stress management, getting out in green space, and making sure you avoid nutritional deficiencies, is the best thing that you can do. I think with supplements, it feels like it gives us some agency over our health. And diet is really easy to say, I'll just eat this and you know, there's a lot of marketing that's misleading. But if you imagine it like this, you know, supplements should supplement a good diet and fill any holes. So for example, certain age groups might require certain vitamins like elderly, pregnant people, people who don't eat meat or exclude specific food groups. But if you're not deficient in something, you can't necessarily make your immune system worked better by taking more, you know, and vitamin C's, the classic example; we do have an increase requirement when we're fighting off an infection. But it's found in abundance in so many foods that we eat every day. You don't need to necessarily spend your money buying vitamin C supplements if you're eating a variety of fresh produce, and if you're not deficient, taking more can sometimes be harmful, and vitamin D is probably the exception because we don't get it from food, we get it from sunlight. And we can become easily deficient based on things like skin colour, age, not going outdoors enough. And its recommended we should all be taking vitamin D regularly.

    [Claudia Hammond] Thank you for that. Now there's a question I would like to put to each of you. So, I'll start with Jenna, since you had your camera on which is; I'd like to ask each of you - this is a hard question! What your predictions are for what will happen next? And where we might be, say in a years’ time. What do you think will happen, Jenna?

    [Jenna Macciochi] It's really hard to predict, because I feel like, there are very few black and whites with this pandemic and with science in general. And the emergence of new variants, etc., keeping us on our toes and raising the bar. I think we have to be driven by the data, not dates. I know in the UK they've released the road map of when life might return to normal. I'm very hesitant to make any assumptions that we will stick to that particular road map because we need the data before we decide on the dates. I do think we will start to transition into an endemic form of the virus. We cannot eradicate it, I mean, smallpox is the only infection that's been eradicated from the earth. So, I don't think that we're suddenly going to eradicate, SARS-COVID 2. And I think, it will still require public health measures in the medium term.

    [Claudia Hammond] Joshua, what is your prediction?

    [Joshua Moon] Same response! I think there's a lot of uncertainty. From what we've seen so far, I can imagine the government is going to stick to, at least to a small extent the dates that they have put forward in their road map. Whether or not that is wise, is a different question entirely. And I will not speak for the government. But I think, I mean, I've always been optimistic. You kind of have to be when your bread-and-butter is disaster. I like to think the very least in the UK that there will be some sort of vaccinated herd-immunity. My worry is more the kind of global level, what does this look like. And the amount of vaccine coverage we have in the global South is particularly worrying. And so, I have deep concerns about maybe this will stop for the global North, for richer countries. I don' think we're going to see a return to normal for the global South for a good long while.

    [Claudia Hammond] Now there's a poll, another poll, I want to do in a second. Let me start asking the poll and then I'll get Ed to answer that question too. But the poll is: Are you optimistic about life feeling more normal during the Summer holidays? And it's a straightforward yes or no, one. So, you can start filling that in. You may be influenced by the answers you're hearing! John, is there anything you'd add to predictions of what will happen?

    [John Drury] Well, first of all there's too many variables. But secondly, I've heard from people whose judgement and I trust that there will be another wave and the question is how big that wave will be. If we get that, after all we've been through, that will be a decline in the already plummeting trust and faith in this Government. I just hope that is the basis of something else.

    [Claudia Hammond] Okay. And Ed, what would you say?

    [Ed Wright] I'd very much reiterate what the other panellist have just said. That this is a global issue and unless you bring the virus under control globally, which is going to takes many years, if it is at all possible then it is going to be a threat wherever you are, because we're so interlinked these days through air travel that it could be re-introduced somewhere overnight when someone comes in on a flight.

    [Claudia Hammond] Yeah, yes. Well, we will get our poll result in a second. Oh, it's ready. The results are ready. Let's have a look. See how much optimism there is. Oh! there is some optimism, 66%, yes and 34%, no. So, we will see what happens whether the optimists are right or not. Let's hope they are. So, thank you so much to all of you. To Jenna and Joshua and John and Ed. And thank you to everyone else for all your questions and for watching. If you have more questions, I'm on Instagram and Twitter @ClaudiaHammond and every month on the BBC World Service in The Evidence. I do an hour show with an international panel of experts answering questions very like this. And I can't tell you how much I've learned from those experts that I haven't heard elsewhere. So, if you want to carry on asking me questions, then you can do that on Twitter or Instagram. Next, we're looking at mental health actually which will be interesting. So, do send any questions, and please do lookout for the next Ask the Expert session from Sussex University, and thank you again to our panel, who have managed to pack in an enormous mountain to this hour. So, thank you very much, everybody. Goodbye.

    [END CARD] Thank you for attending. To find out more about our research and how to support it, please email Follow us on Facebook @sussexalumni, Twitter @sussex_alumni, Instagram @sussexalumni


Dr Jenna Macciochi

Dr Jenna Macciochi is Senior Lecturer in Immunology in the School of Life Sciences; a fitness instructor; and author of two books, Immunity: The science of staying well, Harper Collins 2020, and Your blueprint for strong immunity, Yellow Kite 2022.

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