Review of Vaccine Hesitancy: Rationale, Remit and Methods

"The systematic reviews, studies and consultations revealed many gaps in knowledge about vaccine hesitancy, with a paucity of work in particular from middle and low-income settings, but also revealed useful strategies for moving forward."

This paper summarises the rationale for a Strategic Advisory Group of Experts (SAGE) review of the issue of vaccine hesitancy, its impact and ways to address it, and the convening of a Vaccine Hesitancy Working Group in March 2012. It describes: the methods used, including communication strategies; mode of operation; and advances in the field of research on vaccine hesitancy. It further elaborates and references the work conducted, including a series of products, conclusions, and recommendations that emerged from the SAGE review in October 2014.

As the Related Summaries below elaborate, SAGE was established by the Director-General of WHO in 1999 to provide guidance on the work of WHO concerning vaccines and immunisation. It is charged with advising WHO on overall global policies and strategies, ranging from vaccines and technology, research and development, to implementation of immunisation and its linkages with other health interventions. SAGE Working Groups (WGs) are convened on an ad hoc basis to assemble and review the available data on specific topics and propose draft conclusions and recommendations for SAGE's consideration during its bi-annual meetings.

SAGE's history is described. For instance, in June 2001, SAGE noted that, "although scientific reports stated that there was no evidence of adverse events following immunization (AEFI), the public remained unsatisfied and wanted to be convinced that vaccines had been proven safe. A discrepancy between scientific evidence and perception of risk and difficulties in communication were highlighted. SAGE then endorsed the proposal for the development of a communication strategy to address public concern about AEFI in general, although it was acknowledged that there would always be a marginal yet influential group of people who would not trust information on immunization." To cite another example, SAGE noted that WHO/Regional Office for Europe (EURO) had identified the need for "a methodical and proactive communication strategy to respond to misinformation and anti-immunization activities....Particular challenges to eliminating measles including a lack of political and societal support for the goal, propaganda by anti-vaccine groups, contrary religious and philosophical beliefs, competing health priorities, and problems created by the reform of health systems in some eastern European countries were recognized by SAGE in October 2009." Then, in April 2011, SAGE noted continued non-compliance with vaccination in several areas in Nigeria at high risk of wild poliovirus (WPV) transmission as a cause of concern. In November 2011, SAGE acknowledged that it would be crucial to address vaccine hesitancy in India, classified as a polio-endemic country at that time, as hesitancy was hampering the country's efforts to eliminate polio.

"Given the continuous reappearance of a broad range of issues related to mistrust and non-acceptance of vaccines and the concerns expressed by different countries, the use of effective communication about vaccines with vaccine-hesitant populations was listed in April 2011 as a priority topic for SAGE to address." So, in March 2012, SAGE established the SAGE Working Group on Vaccine Hesitancy. A total of 11 people participated in the proceedings and deliberations of the Working Group. Following an open call for nominations, the experts were selected based on their experience in the field of vaccine hesitancy and to represent a wide array of expertise - including social anthropology, communication and media, immunisation programme delivery, knowledge of vaccination, and experience in addressing vaccine hesitancy at a community level. "Broad representation was assured from all WHO regions and from diverse contexts and backgrounds, as well as balanced membership from developing and developed countries."

The next section of the paper details the Working Group's methods, which included activities such as: literature searches on vaccine hesitancy; review and assessment of models characterising vaccine hesitancy; development and pilot testing of vaccine hesitancy indicators in the WHO-UNICEF (United Nations Children's Fund) Joint Reporting Form (JRF) and at Inter-country Support Team South, East and Central African Regional Immunization Managers' meetings in 2013, in view of the Global Vaccine Action Plan Strategic Objective 2 "that individuals and communities understand immunization as their right and responsibility"; and consultations to discuss hesitancy and its impact with the Global Polio Eradication Initiative (GPEI), United States National Vaccine Advisory Committee (NVAC), communications and marketing experts from industry, and other working groups and advisory committees. Discussions took place via email, monthly conference calls, and 3 in-person meetings of the Working Group. By April 2013, the commissioned systematic review on vaccine hesitancy had been finalised, and based on the retrieved evidence, the systematic review on interventions to address vaccine hesitancy had been initiated. A landscape analysis of organisations working on vaccine hesitancy was conducted.

In the discussion section of the paper, the authors reflect on the iterative process that the Working Group undertook, noting that "[t]he inclusion of a diverse group of experts from different disciplines proved to be very important for critical discussions of the nuances revealed in the reviews, surveys and consultations. Representation of geographic and socioeconomic diversity from all WHO regions was necessary in order to understand the issues from a global perspective, without which the report could have placed undue emphasis on findings from high-income countries, such as those retrieved from the systematic review of evidence....These contributions to understanding, defining and communicating on the topic are seen as an initial step in tackling the continuing and evolving challenges in the field of vaccine hesitancy. The conclusions and recommendations endorsed by SAGE in October 2014...may contribute to efforts to address vaccine hesitancy, particularly by national immunization programmes in all regions of the world when considering the introduction of new vaccines or counteracting the dwindling uptake of well-established vaccines."