Vaccines are one of the most effective public health interventions we have: it is estimated that between 2-3 million deaths are averted each year because of immunisation. The race to find a vaccine for COVID-19 shows just how important they are in protecting our lives and livelihoods. However, despite living in an age of incredible scientific innovation, the potential impact of proven vaccine technology is undermined by sub-optimal uptake. An additional 1.5 million deaths could be averted each year if global vaccine coverage improves.
2020 marks the end of the ‘Decade of Vaccines‘ and the final year of the Global Vaccine Action Plan. In the final assessment report before the close of the decade, the World Health Organization estimated that an additional 20 million children have received vaccinations since 2010. However, uptake of the DTP (Diphtheria, Tetanus and Pertussis vaccination) and the first dose of measles-containing vaccine has plateaued at 85% – below the 90% target set by global health authorities. This problem of under-vaccination is overwhelmingly concentrated in low- and middle-income countries (LMICs): just 10 countries account for 60% of 19.4 million infants that did not receive basic vaccines in 2018.
Based on the volume of media coverage, we might believe that the ‘anti-vaxx’ movement is the primary reason for low vaccine uptake. The recent Wellcome Global Monitor report showed that pockets of distrust in the safety and efficacy of vaccines exist in all corners of the globe. But even in places with a consistent supply of vaccines, practical barriers such as lack of knowledge, forgetfulness, inconvenience and complacency can all contribute to low uptake. Evidence suggests that interventions which focus on addressing these practical barriers to vaccination are more effective at increasing uptake than those aimed at changing attitudes towards vaccines.
In our new report, supported by the Wellcome Trust, we explore existing evidence for behavioural solutions to increase vaccine uptake in LMICs. Compared to high-income settings, there has been relatively little research on ‘what works’ to increase vaccination in LMICs, but several solutions have the potential to be impactful. For example, in Sierra Leone, researchers investigated the effect of highlighting infant vaccine uptake by handing out colourful silicone bracelets. The high visibility of the bracelets communicates a powerful social norm in favour of vaccination and acts as a reminder to parents to take their children to subsequent appointments. The researchers found that the average number of vaccinations received by age 1 was higher in communities where bracelets were given out. ‘Social signalling’ of vaccination using bracelets is now being evaluated in Pakistan.
Those looking to encourage vaccine uptake have also taken advantage of the recent proliferation of mobile phone ownership in LMICs, to deliver what are known as ‘mHealth’ interventions: GSMA estimates that 85% of adults across LMICs now own mobile phones. SMS or recorded voice messages can be sent to caregivers before scheduled vaccine appointments, acting as ‘timely prompts’ reminding people of the importance of vaccination and when to attend. We reviewed 13 studies that evaluated mHealth interventions; 9 of these found evidence that mobile phone reminders encourage vaccine uptake in LMIC settings.
Despite some promising interventions, more research is needed to take them from pilot to policy. In light of the evidence gaps identified in our review, we suggest four approaches to funding future behavioural insights research with the aim of encouraging vaccine uptake in LMICs:
Focus: Fund research into describing and quantifying the prevalence of local behavioural barriers to vaccination
Refine: Fund research to refine and build evidence for promising behavioural interventions to encourage vaccine uptake
Expand: Expand the evidence base by funding research to evaluate behaviourally-informed strategies that have not yet been applied to encourage vaccine uptake in LMICs
Enhance: Use behavioural interventions to maximise the impact and effectiveness of strategies to increase vaccine uptake, for example by improving the effectiveness of vaccine tracking technology
Effective solutions that make routine vaccination memorable, convenient and desirable will be even more urgent in a world changed by Covid-19. In March the WHO recommended that countries suspend routine vaccination where there isn’t an ongoing outbreak. Following this advice, up to 37 countries will suspend their routine measles vaccination campaigns putting up to 117 million children at risk of deadly disease. The vast majority of these countries are LMICs. When routine health services are able to resume, we will need extra effort to identify and immunise undervaccinated children. With more research to refine, expand and enhance the toolkit of interventions to increase vaccine uptake in LMICs, behavioural science can be part of the solution.