The strongest finding of this review was the evidence that extreme unpleasant emotions (fear, panic, hopelessness, shame) had a negative effect on the uptake of public health interventions during outbreaks.
Of note, panic was not followed by action favouring the uptake of interventions in any of the included studies. Within the public health community, and other sectors (especially political), there is still a view held by some that fear- and panic- based campaigns are effective in changing behaviours, and the evocation of fear through emotive language and graphic imagery has been used extensively in public health campaigns (44–46). An expanding body of research has been produced on this issue, some of which even firmly supports that fear-based campaigns are an effective way of increasing people’s self-protective behaviour (47). Despite several study findings that fear-driven appeals and messaging result in non-sustainable, and often undesirable outcomes, including stigmatisation of vulnerable populations, mistrust towards authorities and delayed help-seeking (48), many still support this earlier view that fear-based campaigns are effective(46, 49). The results of this review indicate that, at least in the case of epidemics and pandemics, public health campaigns that appeal to fear are ineffective in motivating protective behaviours in the public.
The analysis in this review showed that unpleasant emotions were evoked much more often than pleasant following public health risk communications, with fear and anxiety being the most common. Moderate anxiety-related emotions covering concepts largely synonymous with “feeling concerned or anxious”, as opposed to extreme unpleasant emotions (fear, panic, shame, hopelessness), were significantly positively correlated with the uptake of interventions, clearly pointing to a direction for how the public can be motivated to take action in response to the risk of an epidemic. Given the detrimental effect of fear on following public health guidance and the uptake of interventions found, there is a demonstrable need for public health professionals to consider moderate emotional responses to public health strategies and crisis communications as a means by which health behaviours can be proactively influenced.
The emotion of empathy emerged as a key motivator for action in this systematic review, being positively and significantly associated with uptake of public health interventions, primarily following recommended measures and uptake of personal prophylactic measures. Despite the fact that few studies have researched how pleasant emotions may lead to uptake of intervention outcomes in epidemics, the trend was strong, with eight out of ten occurrences leading to uptake of interventions. More research is needed to confirm this trend. In keeping with these findings, an empathic response to the threat of SARS was found to predict increased adoption of the recommended health precautions, independent of the level of perceived viral threat (50). This finding was also observed in a study of response to the West Nile virus (51) and a study in the H1N1 pandemic setting during which the pandemic vaccine was produced and distributed (52). These findings suggest that empathic responding may modify the effect of the stressor itself to facilitate protective health behaviours (50, 52).
This is consistent with the research on prosocial behaviours, in which empathy has been well documented as leading to more effective social functioning, that benefits both the direct recipients of actions and behaviours and the wider society (53, 54). Recent research on Covid-19 illustrates the importance of altruistic, prosocial motivations in protective behaviours, with appeals to protect one’s community found to be stronger predictors for engaging with preventative public health behaviours than messaging promoting protecting oneself (55, 56). Notably, Heffner et al. found prosocial messaging that produced a strong, positive emotional response led to increased willingness to engage with preventative behaviours (57). Pfattheicher et al. have also found that inducing a prosocial emotional process, empathy for those most vulnerable to Covid-19, relates to motivation to adhere to preventative measures, bolstering the evidence of empathetic emotions’ potential to promote public health guidance adherence (58). Thus, open communications strategies rooted in care and compassion could help facilitate more protective and altruistic decision-making by the public, and public health communications should be refined to incorporate and acknowledge the important role that empathy and compassion can play.
This finding is particularly relevant in the context of vaccination uptake in the current Covid-19 pandemic, in which eliciting empathic responses may be crucial. Vaccination has long been an emotionally charged subject, and public health professionals attempting to combat vaccine hesitancy need to work with awareness of the influence emotions play in vaccine risk perception and move away from the belief that the evidence will speak for itself (56, 59, 60). In the current climate of concern over Covid-19 vaccine safety and availability prompted by the expedited approval process and vaccine misinformation campaigns which have thrived online over recent years and during the Covid-19 pandemic, an empathetic and open style of communication, which is the most effective in galvanising the population to take positive action or refrain from a harmful act, could be employed effectively (14, 56). A recent study has already identified eliciting empathy for those most vulnerable to the virus as a potential means to improve intentions for vaccine uptake (61). Empathy and caring show honesty, dedication and openness, all of which are essential elements in persuasive communications and further research in this area is needed (62).
Despite the included papers covering a range of nations and continents, in the case of studies in African nations (largely focused on Ebola) only extreme unpleasant emotions were assessed, with a complete lack of associations on taking action on uptake of interventions. There were no relevant studies conducted in Central and Latin America, although a recent study has assessed the role of hope and trust amongst healthcare workers (37).
Limitations
This review had some anticipated limitations: emotions were never the primary variable in the included studies, quantitative data were scarce, it was only rarely reported where certain emotional determinants were counterproductive to an outcome, and the actual definitions of emotions in the included studies were far from systematic and consistent. Since most of the quantitative data were drawn from cross-sectional studies, causal inference cannot be made based on the observed associations between the various emotions and intervention uptake. Furthermore, the outcome in the studies (intervention uptake) was studied in a dichotomous way (yes or no), and no effect sizes were available. Hence, for the data synthesis, we did pool some very diverse data, and the analysis conducted seems to have been all that was feasible given the significant heterogeneity between studies and what was reported. In addition, effect sizes were not recorded in the included studies for the variables and outcomes studied and individual participant data were not assessed. However, the review derived its evidence from a total overall sample of over 80,000 subjects across a variety of nations, continents and contexts. An important limitation of the review is the narrow assessment of emotions and outcomes in the included studies, which fails to capture the depth and breadth of the human experience in response to outbreaks. This can only be addressed by a more in-depth study of outbreaks as they occur in local regions.
Future Research
Empathy and hope were the two pleasant emotions studied that resulted in an uptake of public health interventions. The outcomes evoking pleasant emotions, such as empathy, hope and compassion, remain under-researched and poorly understood in public health and warrant further study. The emerging research on the positive role of empathy in promoting physical distancing and vaccination intention during Covid-19 is a valuable contribution to this area and strengthens the case for further research (58, 61).
Going forward, new research frameworks will be needed to produce a more nuanced understanding of how emotional responses are born and manifest themselves during health crises. This is particularly relevant to empathic and prosocial responses to distress, which may predict distinct behavioural responses to the threat of global viral infections. Research indicates that coping strategies are associated with engaging in health behaviours in response to health threats. Future research should expand on how coping strategies are investigated and investigate the potential effectiveness of promoting effective coping and decreasing maladaptive strategies in response to future health threats (51).
More sophisticated and targeted research and evaluation analyses are also needed to understand which outbreak responses are most effective. Comparative psychobehavioural surveillance and analysis could yield important insights into generic versus population-specific issues that could be used to inform, design, and evaluate public health infection control policy measures (63). The Appraisal Tendency Framework, which proposes a theoretical connection linking one’s discrete emotions with their cognitive appraisals, could be used more in public health (64). Researchers should use the opportunity of real-world infectious disease outbreaks – such as the current COVID-19 pandemic – to study emotional regulation in natural settings, that is, what strategies individuals use to manage their emotions in the face of risk (65).
Given identified differences between pleasant and unpleasant, moderate anxiety-related and extreme unpleasant emotions, and some variability by infection, outcome and region in the findings of this review, a nuanced understanding of how emotional determinants determine public responses and health outcomes at a local level is needed, and there is much potential learning to be recorded by the various national responses to COVID-19.