In the fifth and final paper in the Series, Dr Heidi J Larson (London School of Hygiene and Tropical Medicine, UK) and colleagues analyse the complex range of factors that are causing loss of public confidence in vaccines: the so-called vaccine confidence gap. The authors say: "The 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."
They add: "Public decision making related to vaccine acceptance is neither driven by scientific nor economic evidence alone, but is also driven by a mix of psychological, sociocultural, and political factors, all of which need to be understood and taken into account by policy and other decision makers. Public trust in vaccines is highly variable and building trust depends on understanding perceptions of vaccines and vaccine risks, historical experiences, religious or political affiliations, and socioeconomic status."
Larson and colleagues highlight the powerful effect that the internet and social media has had on the debate on vaccines, enabling groups either for or against vaccination to organize themselves into highly effective international organisations capable of rapid dissemination of information (including misinformation and rumours). As with infectious diseases, where surveillance is essential for disease control, systematic monitoring of dynamic and evolving vaccine rumours, concerns, and refusals is crucial to guide prompt responses to build and sustain public confidence. Such a surveillance system is being trialed at the London School of Hygiene and Tropical Medicine.
A number of case studies are explored that highlight how vaccine risk concerns were prompted and sustained by individuals. During 2010 in India, Puliyel and colleagues (representing a cross section of paediatricians, healthcare activists, public health teachers and bureaucrats) challenged the Indian Government's plan to introduce Haemophilus influenzae type b vaccination into the country's schedule, on the basis that the disease burden in India did not justify the expense. Puliyel has expressed alarm that some parts of Indian society have taken his views to be part of a broad antivaccination movement, despite the fact he has been pro-universal vaccination in India all his working life. In another case, in 2003, religious and political leaders in Nigeria boycotted the polio vaccine, after raising fears it could spread HIV and cause sterility. This boycott was a wake-up call for the Global Polio Eradication Initiative to better engage with these community leaders.
The authors say: "Information alone will not stop public distrust and dissent against vaccines…Trust is built through dialogue and exchange of information and opinion."
They add: "New methods of communication, dialogue, and engagement are urgently needed across all vaccine stakeholders—vaccine experts, scientists, industry, national and international health organisations, policy makers, politicians, health professionals, the media, and the public. No single player can reverse the vaccine confidence gap."
They conclude: "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."
Dr Heidi J Larson, London School of Hygiene and Tropical Medicine, UK. T) +44 79 4720 4226 E) heidi.larson@lshtm.ac.uk / heidijanelarson@yahoo.com
Journal
The Lancet