‘We will have to live with the risk of Covid-19… but Psychology has much to say about that risk’
Kavita Vedhara on the fascinating world of vaccine adjuvants and more.
04 May 2020
In the absence of an effective vaccine, and a vaccine programme that can cover the world’s population, people will continue to become infected with Covid-19. However, the course of this disease is far from uniform. It has been suggested that large numbers of people are infected but remain asymptomatic. Others have only mild disease, and at the other end of the spectrum it’s estimated that 3 per cent will die. What factors determine whether you get infected and the severity of the disease? The current data are pointing to risk factors such as being male, lower socio-economic status, age and ethnicity as being important. But none of these are modifiable. If you are an older, Asian, blue-collared worker, the data will not fill you with optimism. However, psychological science, and specifically psychoneuroimmunology, suggests that there may also be modifiable influences on whether you get Covid-19 and the severity of the illness.
The early work of Sheldon Cohen and colleagues demonstrated that when you experimentally expose people to the common cold, levels of stress influence not only who becomes infected, but who becomes symptomatic. These findings have been replicated many times and suggest that there will be huge potential for psychologists to elucidate the role played by psychological factors in determining who gets Covid-19, and the course of the disease.
I am not suggesting that this will be about stress alone. The pandemic will force us to embrace more sophisticated models of psychological influences on health. At a time when social distancing (or physical restriction, as it is now being called) has been mandated, it means that some of our more powerful weapons in the armoury against stress (e.g. social support) are not only unavailable, but their corollaries (e.g. loneliness) may serve to compound the effects of an already stressful situation.
There probably won’t be an effective vaccine
But what about when we find the holy-grail and a vaccine is developed? At the time of writing, vaccine trials have already begun. But having a vaccine and having an effective vaccine are two very different things. The ugly truth about vaccinations is not only that they usually take decades to develop; but that we have never developed an effective vaccine against a coronavirus before. Furthermore, even when we develop effective vaccines, it is common for them not to be universally effective – just because you are vaccinated doesn’t mean you are protected against the disease. Perhaps the best example of this is the seasonal flu vaccine, where some studies suggest that its effectiveness among older people may be as low as 17 per cent.
None of that sounds very optimistic, so let me return to my glass being half-full. When the vaccine comes there will be huge opportunities for psychological science to play its part. The first, and one closest to my heart, will be the potential for psychological and behavioural factors to influence the effectiveness of vaccines. The literature is replete with evidence from observational and intervention studies which show that our ability to produce antibodies in response to vaccinations (antibodies are how vaccines confer protection) is associated with our mood, physical activity and aspects of diet among other things. The size of these effects are modest, but some research suggest they are equivalent to the effect sizes of statins; on a population level, these effects are clinically important. Understanding what the preeminent psychological determinants of vaccine effectiveness are, and then developing suitable interventions to enhance these, will be a critical area of research and practice.
The second area concerns that group of individuals often referred to as the ‘anti-vaccers’: people who refuse vaccination. Given the highly infectious nature of Covid-19, a vaccine programme will only be effective if we can vaccinate the majority of the world’s population – perhaps greater than 90 per cent. So there will be an urgent need to better understand the cognitions and social influences (yes, I am thinking of Donald Trump) that lead people to make these behavioural choices and to develop interventions which will increase the uptake of any future vaccine.
Other unintended consequences and opportunities
There are people who are better informed than me who will drive forward the science and debate in various other areas of psychology and science. But I can’t resist the opportunity to mention just four that I am beginning to have opinions on. And as with all the best disclaimers, the opinions expressed here are not necessarily the opinions of anyone else… I share them only in the interest of provoking healthy debate.
It was obvious very early on that the only way to contain the virus would be to restrict the movement of the population. This has been largely very effective. All the data show that the vast majority of people have adhered to the ‘rules’. But we didn’t achieve this by developing individualised interventions that spoke to our cognitions, or developing complex logic models based on theories. Nor did we have the privilege of spending years on developing the intervention. This was a change in public policy backed up by law enforcement. The parallels with the widespread adoption of behaviours such as wearing seat-belts and drink driving are clear. That’s not to say health psychology has become irrelevant. It has played its part in informing the messaging, the timing of the lock-down, and it will no doubt play its part in sustaining social distancing and helping people adapt to a new socially distanced normal. But is it time to examine whether other threats to population health, such as obesity, require changes in public policy, such that psychology’s role is not to support people in initiating the required changes in behaviour, but in sustaining them? Or do we consider that the role of the state should be restricted to only those diseases where the threats are immediate and where our actions directly impact on the health and well-being of others? At a time of rapidly vanishing resources, the answer may be unpalatable.
Multidisciplinary research and the tension between the basic and applied sciences
Our response to the pandemic has raised questions about the modelling that informed the early decisions. Did we lock down soon enough? Should we have abandoned contract tracing so early? Why did we not mandate that people displaying symptoms should self-isolate for 14, rather than 7, days? Or should we, as the unrelentingly impressive Prime Minister of New Zealand, Jacinda Ardern, said, have ‘gone hard and (gone) early’?
Raising these questions does not negate the importance of the modelling. It is important to acknowledge that the modelling played a vital role in shaping the government and NHS’ response. It enabled them to do the unthinkable and prepare the NHS’ critical care capacity for the relentless wave of Covid-19 patients. Indeed, modelling has and will continue to make hugely important contributions in many areas of health.
However, the pandemic has also highlighted, for me at least, the potential limitations of modelling. Would we have been better to take a more genuinely multidisciplinary approach? Other disciplines were undoubtedly ‘in the room’ and we should not be so naïve as to think that the scientists made the decisions: ‘advisers advise, but the politicians decide’ (a now familiar refrain). But I am left wondering if the results from the modelling were preeminent? Did all disciplines have an equal voice? Also was sufficient consideration given to the more traditional cornerstones of science i.e. to observe and experiment? It is evident that there were lessons to be learnt from observing the pandemic unfold in other countries. What happened when other countries went into lock-down? How long did it take them to ‘flatten their sombreros’? What can we learn about the potential effectiveness of interventions such as facial coverings, and widespread community testing and contact tracing, by examining the incidence and spread of the disease in those countries that adopted these measures? Hindsight affords us 20-20 vision and everyone can be wise after the event. But for me, a good outcome would be the further disintegration of disciplinary boundaries as well as a recognition that applied sciences flourish only when based on the best available basic science. This is true for all science, but perhaps of particular relevance to the modellers and those of us in the behavioural sciences given our replication crisis.
The role of technology
Six months from now any return to normal will almost certainly rely in part on real-time assessments of our risk of disease and our ability to get people to make rapid changes in behaviour. Countries such as South Korea who appear to have contended with Covid-19 more effectively than most introduced technology to support them very early on. An app used by large swathes of the population is able to update people on episodes of disease local to them. If you have travelled on a bus which was taken by someone who tested positive for Covid-19, you are alerted and urged to get tested. These alerts are regular and frequent and seemingly effective in prompting a behavioural response (to get tested and/or to self-isolate).
What are the implications for health psychology of the widespread adoption of such technology? Well, Psychologists have known for some time the value of real-time or momentary assessments but it is true that we still tend to rely (and I include myself in this) on retrospective accounts. Most measures of mood, for example, ask you to report how you have felt in the past few weeks. Most measures of behaviour ask you to report what you have done historically, not concurrently. This pandemic will not only drive forward the technological innovation to make momentary assessment possible, simple and affordable, but acculturate the world’s population, and psychologists, in the need for such assessments, as well as their potency in producing behavioural change. This will be a fantastic innovation for many of us and will vastly improve the rigour and effectiveness of our science.
How health psychology positions itself among other health sciences
I, among others, have been an advocate for some time of psychological interventions which can be used to optimise existing treatments: so-called ‘psychological adjuvants’. Psychological interventions to promote the effectiveness of vaccines, or recovery from surgery, are nice examples of this. But the pandemic highlights for me that the reverse is also true i.e. that some psychological interventions might be more effective if they are not delivered in isolation but combined with other ‘treatments’. For example, there is much debate about the mental health consequences of the pandemic. Let’s consider just the example of how best to manage people’s stress, anxiety and worry about returning to work, sending their children back to school etc.? When that time comes in the (hopefully) not too distant future, should we be thinking only about psychological interventions that can be delivered at scale? I think not. Interventions to reduce these negative feelings would, in my view, be more effective if combined with other interventions. Two obvious candidates spring to mind. The first is face coverings. There is much debate regarding the effectiveness of face coverings in protecting us against Covid-19 and while there is no randomised controlled evidence to support their use, it seems we in the UK will move toward adopting them like many other countries have. But whether or not they protect us from Covid-19 is not their only potential benefit. We can hypothesise that anxiety reduction programmes would be more effective if combined with the use of face coverings. This combined approach would give people the cognitive skills to manage their affective response, while the face coverings could provide the reassurance they will need to manage their fears and participate in society once more.
Similar adjuvant potential could be offered by antibody tests. These tests are currently not available. But once tests have been developed which provide a reliable way of telling us if we are immune to the virus, then they could play a pivotal role in enabling individuals to return to some semblance of normality. Again we could hypothesise that combining antibody testing with interventions aimed at cognitive restructuring and/or stress management would together be more efficacious than a psychological intervention alone. Perhaps we too should be wary of perpetuating dualism by thinking only of the mind, when thinking about health.
Finally, a word on Gavi and Corona. Six months ago those words represented alcoholic indulgences best enjoyed on far flung beaches in the company of colleagues (you know who you are), family and friends. Six months from now those words will probably make me think first and foremost of the vaccine alliance and of a disease that has shaped our lives like no other. But I will hold on to the hope that a crisp glass of Gavi on a sun-drenched beach will once again be part of my future…
- Kavita Vedhara is Professor of Health Psychology at the University of Nottingham.
- See also our November 2017 interview.