Vaccine Confidence: The Keys to Restoring Trust

"The success of any vaccination strategy is determined by the people's confidence in the vaccination system and their trust in health authorities; otherwise, vaccination strategies might become counterproductive..."

With a focus on childhood vaccination, this article explores causes and implications of the increase in vaccine hesitancy (VH) in developed and developing countries and proposes evidence-based solutions to improve vaccine confidence.

It begins with a look at the current situation and grounds for low vaccine confidence, including:

• Misinformation and hoaxes - Studies have found that, in developed countries, the internet and social media have played a central role in the advancement of anti-vaccination movements and in shaping vaccination decision-making. However, misinformation about vaccines spans all settings. Fabricated information (hoaxes) about vaccines may gain traction when spread by opinion leaders. For example, in Nigeria, in 2003, rumours that the oral polio vaccine (OPV) was an American conspiracy to sterilise Muslim girls and spread human immunodeficiency virus (HIV) resulted in the suspension of OPV use in 5 northern Nigerian states, causing a nationwide epidemic and re-infection of previously polio-free countries in Africa and beyond.
• Loss of trust and risk communication challenges - Several unfortunate events have negatively influenced public opinion and trust in vaccination and vaccine safety, both in developed and developing countries. For example, in Europe, the 2009 H1N1 influenza outbreak - deemed a pandemic by the World Health Organization (WHO) - had far fewer consequences than initially anticipated, and the Council of Europe considered the national budgets spent to combat it to be disproportionate and unjustified. Consequently, the WHO criteria for a pandemic was subject to public controversy and received widespread media coverage. Public trust in the authorities was challenged, and low adherence to subsequent influenza vaccination campaigns was recorded.
• Healthcare provider (HCP) involvement - HCPs are a key source of information about vaccination, and the interaction between patients or their parents and HCPs is at the core of maintaining confidence in vaccination. It has been shown that HCPs who are knowledgeable about vaccines are more confident and more likely to recommend vaccination. Studies have found, however, that HCPs' knowledge about vaccination issues is variable and that training in vaccinology is poor or non-existent in medical curricula in many countries. Beyond knowledge, the HCPs' attitude is important to convey trust. One study found that vaccinated HCPs are more likely to recommend vaccination to their patients than unvaccinated colleagues.
• Complex dynamics of immunisation - Although vaccines do not always produce a full immune response, they may nevertheless lessen disease symptoms, as seen with influenza, pertussis, and rotavirus vaccines. This protective effect may not always be fully appreciated by HCPs and the general population and, as argued here, should be emphasised.
• Healthism - Some practitioners (homeopaths, chiropractors, and naturopaths) have a negative view of vaccination and advise their clients accordingly.
• Skepticism toward science - Research has shown that belief in science is decreasing, and the willingness to accept nonscientific approaches is increasing, all around the world.

Having outlined the consequences of low vaccine confidence, both medical and economic, the authors propose some solutions, including:

• Regaining trust through: (i) provision of valid information (e.g., the pharmaceutical industry could do more to address people's concerns with information suited to different audiences, such as video summaries of scientific articles and plain language summaries of clinical trials) and (ii) international and cross-sector partnerships (e.g., partnerships between health authorities on an international level with the education sector, social partners, and public and private healthcare sectors could optimise awareness-raising campaigns, produce modern tools to increase vaccine confidence, and provide support to economically poorer countries).
• Using the media, including the internet, by, for example, raising positive voices, potentially using community influencers, and sharing a cross-sector unified message presenting vaccine acceptation as the social norm, while acknowledging and positively valuing those who do accept vaccination. The authors stress that communication planning must not be limited to crisis management but, rather, should be ongoing, proactively providing messages directly geared to respond to critical public concerns, taking into account social and cultural characteristics as well as geographical influences.
• Increasing HCP preparedness through training courses that support them in fulfilling the requirements of the important information and communication process of recommending a vaccine. "To provide the evidence that is needed by the parents to make informed decisions without oversaturating them with information, it is important that HCPs develop their ability to listen to parents' concerns and communicate clear and understandable messages. Such an approach is key in building trustful communication between parents and HCPs and is one of the principles of motivational interviewing..." HCPs need not only communication tools but the required time for information exchange. Furthermore, "involving HCPs in the process of developing vaccination recommendations would improve their understanding and engagement in implementing them..."

In conclusion: "Incorporating the progress and results of vaccine research into successful vaccination programs, and replacing misinformation with evidence-based communication is crucial in improving vaccine confidence and requires a multidisciplinary, cohesive, targeted, and managed approach."