Addressing the Vaccine Confidence Gap

"Although communication of candid, evidence-based information to the public about the safety of specific vaccines and their benefit-risk ratios is crucial, this information alone will not stop public distrust and dissent against vaccines..."

Published in the Lancet, this paper discusses some of the characteristics of the changing global environment that are contributing to increased public questioning of vaccines and outlines some of the specific determinants of public trust. The authors argue that "[t]he vaccine community demands rigorous evidence on vaccine efficacy and safety and technical and operational feasibility when introducing a new vaccine, but has been negligent in demanding equally rigorous research to understand the psychological, social, and political factors that affect public trust in vaccines."

Following an introductory section, the paper explores the reasons behind the "waning public trust in vaccines". Panel 1 in this section presents a framework for analysing the development of public concerns about vaccines. Public concern can be prompted by factors such as: adverse events following immunisation, publication of new research, new recommendations or policy change, new products, and political motivations (i.e., purposefully spreading rumours to undermine the government, other providers, or producers of the vaccine). Factors that sustain public concern listed here include: global spread of vaccine-related rumours, frequency of rumours, media reports that amplify any prompter of public concern, historical bad experience that lowers public trust, socioeconomic marginalisation, and previous existence of self-organised community groups that can repurpose their experience to address vaccine concerns.

One specific communication-related reason discussed in this section of the paper is new media and horizontal communication. Namely, "[d]emocratisation movements and the advent of the internet have changed the environment around vaccines from top-down, expert-to-consumer (vertical) communication towards non-hierarchical, dialogue-based (horizontal) communication, through which the public increasingly questions recommendations of experts and public institutions on the basis of their own, often web-based, research." Furthermore, "[t]he internet, social media - which allows interactive exchange between many users - and mobile phone networks have shifted the methods and speed of communication substantially, allowing information about vaccines and immunisation to be gathered, analysed, and used - especially through blogs - very differently compared with even a decade ago. The amount of information available has increased greatly, including scientifically valid data and evidence-based recommendations alongside poor quality data, personal opinions, and misinformation."

The next section explores determinants of public trust in vaccines, described here as "a complex issue that often has many converging determinants. Research into environmental-risk communication has identified three factors that affect the extent to which an individual or institution is trusted: perceptions of knowledge and expertise, openness and honesty, and concern and care....The credibility of vaccine information, for example, is influenced by the perceived trustworthiness of the messenger - whether a government authority, the vaccine industry, a health provider, a friend or colleague, or the media." In this context, the authors urge that, "[t]o improve understanding and address determinants of public trust in vaccines, and the potential effect of these determinants, research is needed not only into individual determinants of trust, but on understanding what mix of factors is most likely to sustain, or damage, public trust." Several case studies are provided to illustrate this recommendation, all of which highlight examples (e.g., oral polio vaccine in Nigeria) from around the world of how vaccine risk concerns were prompted and sustained by individuals - from religious leaders to scientists and health experts, governmental and non-governmental institutions, religious and other interest groups, and the media. "The tipping point, whereby vaccines were refused or programmes were disrupted because of fears, was due to a convergence of events..."

Communication-centred recommendations offered here in going forward include:

• To sustain or restore confidence in vaccines, a thorough understanding is needed of the population's - or subpopulation's - specific vaccine concerns, historical experiences, religious or political affiliation, and socioeconomic status.
• Core principles to be followed by all health providers, experts, health authorities, policy makers, and politicians include: engagement with and listening to stakeholders, being transparent about decision-making, and being honest and open about uncertainty and risks.
• "Extremist antivaccination groups whose minds will not change will exist. Many people - the majority - who accept vaccines could change their mind. The focus should be on building and sustaining trust with those who accept and support vaccines, while working to understand and address the growing confidence gap."