Skip to 0 minutes and 8 secondsToday, I'm joined by Rhiannon Edge, who's a graduate student at Lancaster Medical School studying epidemiology and social networks in relation to flu vaccination. Perhaps we could start, Rhiannon, by explaining what epidemiology is. Well, epidemiology is the study of how diseases might spread through a population. And my research looks particularly at the spread of disease through social structures, for example, like contact structure. Right. So how is vaccination done in the National Health Service System in the UK? Well, the NHS follows the WHO guidelines, the World Health Organization guidelines, and also recommendations from the Chief Medical Officer for England, which recommends to vaccinate anyone in a high risk group and health care workers themselves. Right.

Skip to 1 minute and 0 secondsAnd when does this vaccination roll out begin? Well, each year just before the flu season. So about October, November time, we start recommending people to get vaccinated. So the idea is to get all the people who are judged to need a vaccine, vaccinated before the flu arrives, which will probably be around Christmas time or slightly before. Yeah. Exactly. So once you've had your flu vaccination, how effective do we actually expect the flu vaccine to be in the vaccinated population? Does it give it complete protection or partial protection? No. It doesn't, unfortunately. So each year the flu virus changes drastically.

Skip to 1 minute and 40 secondsAnd before they design the flu vaccine, the World Heath Organization tries to essentially guess at which strains of flu will be circulating the following year. So the vaccine is almost never 100% effective. So this vaccine choice is based on what we've seen circulating in previous years. And some experimental or theoretical modelling about where antigenic drift is perhaps going-- Yeah. Exactly. --and actually, we're trying to guess ahead of the virus what virus will be like. We use past seasons to decide that, and then what's happening on the other side of the continent. So for example, Australia will be in their flu season while we're in our summer season. And they tend to be quite good.

Skip to 2 minutes and 27 secondsIt tends to be around 70% effective. Occasionally the flu virus will do something unpredictable. Yes. And it did this last winter, 2014/ 2015. Yeah. Unfortunately I think we were lower, considerably lower, something like 3% effective. Right. 3% from 70% is really quite a drop, isn't it? Yeah. Yeah. We don't get it right all the time. And I think in the last decade, half of the times we've had mismatched vaccines. Now, that doesn't mean that it's completely pointless again, the flu vaccine, even with a mismatched-- even with a mismatched strain.

Skip to 3 minutes and 12 secondsThere are still some benefits that you tend to have, less severe symptoms, for example. So when we're designing a trivalent vaccine, what sub types or strains would go in a trivalent vaccine? So you would have a H1N1 a H3N2, and a seasonal influenza B. Right. And for the quadrivalent vaccine, what's the fourth component that would go in? We add in an additional influenza B strain. Right. In the "at risk" population, we've already defined people for instance - elderly people, very young children, and those who have an underlying medical condition, especially respiratory one, like asthma, or something like that, who are in need of some immune support against a flu attack.

Skip to 3 minutes and 57 secondsBut what about health care workers, because they are recommended to be vaccinated as well? Yeah. Yeah. That's true. The Chief Medical Officer for England recommends that health care workers receive the seasonal influenza vaccine. And it's partly to protect themselves from getting ill - they come into contact with a huge number of viruses and pathogens that we wouldn't normally come into contact with. So they're much more likely to get it than members of the general population just by being in contact with patients. That's the logic, and also to protect their patients. So doctors don't necessarily want to be passing on influenza to very sick patients.

Skip to 4 minutes and 36 secondsThe other issue is preventing NHS staff from having days off sick, for example because influenza takes pressure off the NHS Yes. Yeah. Yes. And how successful have the NHS been in encouraging their front line employees at least to take up the vaccine? Well, uptake is about 55% of health care workers receive the influenza vaccine, which is better than most of Europe. So we're doing quite well. There's still quite a big debate as to whether heath care workers should have to have the flu vaccine. A lot of them aren't in the high risk category themselves. It's not obligatory here, whereas I believe in some in US states, it is obligatory. Yeah. Exactly. Mandatory over there.

Skip to 5 minutes and 22 secondsSo your own research, Rhiannon, is particularly related to this issue of uptake of vaccine among NHS workers, National Health Service workers. What does that involve? Yeah. That's right. So my research is about social networks and epidemiology, essentially. So first-- Perhaps we should just define what a "social network" here is in this context, because I'm sure a lot of people think that social network is your Facebook friends. But that's not what you mean. That's not exactly what I mean. So social network could be anybody that you come into contact with during the day. So we're having a connection here because we're talking, for example.

Skip to 5 minutes and 58 secondsIt's not necessarily people that you are Facebook friends with but never see because there's very little room for-- So it's really a social contact in the old fashioned sense of somebody that is in the same room as you. Yeah. For an epidemiology sense. And so first of all, I would look at whether there's key individuals within that sort of a social network that may be more important to vaccinate, so maybe they spread disease to lots of people, or they have a high potential to reduce disease spread.

Skip to 6 minutes and 29 secondsSo it would be easy to imagine that perhaps a GP in a practice on a busy week would see lots of people coming in, would be somebody that would be at the centre of a very large network. But how do you quantify that? How do you put some numbers on it? Well, my research specifically looks at foundation doctors. So I have mapped out their social networks, which other doctors they come into contact with, as kind of a proxy of how many people they see during the day, because I am interested in spreading disease between doctors too, doctor to doctor.

Skip to 7 minutes and 4 secondsSo a foundation doctor, we should explain is someone that's working within a larger health system, not just a general practitioner, but might include hospital doctors, and anybody that's working within an area health network. Yeah. So foundation doctors are in their first two years after graduating from medical school and tend to be doing training in hospitals. Yeah. So I'm looking at whether or not those individuals are key in that network. And the same ideas can be applied to basically anybody. So you talked about the GPs maybe being important because they see a lot of patients. But you also have to consider the receptionist out on the front desk, who is probably seeing the same number of patients.

Skip to 7 minutes and 48 secondsSo they are quite transferable ideas from a disease spread perspective. The other element is about a social mechanism. So rather than just coming into contact with people and building a social network that way, it's anybody that might influence your behaviour. So for example, groups of people might choose to associate themselves with others that are like themselves. So smokers might be friends with other smokers, for example. They might go on smoking breaks together. My theory is about whether or not people act in a similar way with regards to vaccination, and so whether you're finding clusters of individuals that all have the same vaccination attitude.

Skip to 8 minutes and 31 secondsSo it's a little bit about dissecting the way that people are influencing their social network as opposed to the idea that social networks tend to be formed for people who already share the same opinions. And influences, it's as if birds of a feather are flocking together, rather than somebody spreading an idea within a particular group. Well, that's exactly it. Yeah. And then the effects of that on disease spread. So it's kind of a two-pronged approach with the disease spread through the network on one side, and then attitudes on-- Yeah. OK. And how do you think that this might feed forward into changes in NHS practice?

Skip to 9 minutes and 14 secondsWe mentioned that earlier on, that we're probably not going to have a compulsory system, simply because it's not in the NHS culture to enforce something like that against the will of its employees. But on the other hand, we would like to get up from 55% to something higher than that. So how can you use the knowledge of this social networks to promote vaccine uptake? So one of my ideas is to potentially identify proxies for influential individuals. So people with a large number of contacts might be important for us. And if we can some how measure their demographic factors there may be all of the most important people in our network are surgeons.

Skip to 10 minutes and 2 secondsSo maybe we should target our vaccination campaigns towards those, for example. So thanks for joining us today, Rhiannon. It's been very interesting, as well as getting an insight into your own cutting-edge research on how we study vaccination, essentially, and its uptake. It's also been very useful background about vaccination in general and how a health service system decides how to tackle this massive task that we have every 12 months. No problem. Thank you.

Social Networks and Vaccination

In this video, I’m joined by Rhiannon Edge, a postgraduate research student at Lancaster Medical School. Rhiannon discusses her research work on vaccination patterns for influenza among employees of the National Health Service in the UK.

Such medical workers are not legally obliged to be vaccinated, but 55% choose to do so. How we might increase that 55%, and how that 55% are connected to each other, is a major component of Rhiannon’s research.

Also listen to what Rhiannon has to say about vaccine efficacy, as that is a component of the calculation we are going to perform based on Prof. Glynn’s lecture.

Some of Rhiannon’s research has recently been published, and the links can be found below.

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This video is from the free online course:

Influenza: How the Flu Spreads and Evolves

Lancaster University