Vaccine Hesitancy

by

Eve Dubé, Noni MacDonald

• LAST REVIEWED: 23 August 2017
• LAST MODIFIED: 23 August 2017
• DOI: 10.1093/obo/9780199756797-0171

Introduction

Vaccines are one of the greatest public health achievements. It is estimated that vaccination programs prevents 2–3 million deaths each year. Despite a clear and unambiguous scientific and medical consensus on the benefits of vaccination, there are some people, including health-care providers, that are skeptical about vaccination. The public health success of vaccination means that new generations are unaware of the risks of many vaccine-preventable diseases and their concerns are now often concentrated on the individual vaccines themselves. Although acceptance of vaccines is still the general pattern worldwide, public health authorities are more and more concerned that vaccination programs are losing momentum. Recent outbreaks of vaccine-preventable diseases in both high and middle-income countries have been linked to under-vaccinated or non-vaccinated communities, showing the dramatic consequences of a decline in vaccine coverage rates on individual and population health. During the early 21st century, the concept of “vaccine hesitancy” has received increasing international attention. This concept represents a shift from the dichotomous “anti- vs. pro-vaccine” perspective to an approach characterizing behavior on a continuum ranging from active demand for vaccines to complete refusal of all vaccines. Vaccine-hesitant individuals are a heterogeneous group along this continuum; they can occupy different (or many) places along this continuum. A vaccine-hesitant person can delay, be reluctant (but still accept), or refuse/accept some or all vaccines. Vaccine hesitancy is an individual state that is resulting from a multitude of individual factors (e.g., knowledge, values, past experiences, health beliefs, etc.), but it is also the result of broader historical, political, and sociocultural influences. This article highlights research that has examined factors leading to vaccine acceptance, hesitancy, and refusal. An important limitation of this review is that most of the peer-reviewed literature on this topic is coming from North American and western European countries, and low- and middle-income countries are under-represented. In addition, only literature written in English or in French has been reviewed. Finally, although, access to vaccines and vaccination services (i.e., “the supply-side”) is crucial in understanding why people are not receiving the recommended vaccines, this article focuses on the “demand-side” of vaccination, which refers to how vaccine recipients and vaccine providers understand and engage in immunization.

General Overviews

As described in Blume 2006 and Moulin 1996, resistance to vaccination is as old as vaccination itself—people have been reluctant to accept vaccination since Jenner first scraped cow-pox blisters and inoculated people in the early 1800s. The topic of vaccine acceptance and resistance has always been of interest to medical and social sciences researchers. However, during the early 21st century, an increasing number of overviews related to this subject have been published; the breadth and depth of articles reflecting a broadening of the field of study (e.g., Cooper, et al. 2008; Omer, et al. 2009; Leask 2011). The growth in comments, reviews and studies around “vaccine hesitancy” is also noteworthy (e.g., Dubé, et al. 2013; Larson and Schulz 2015; and Leask, et al. 2014). In August 2015, the journal Vaccine devoted an entire supplement on the subject, presenting the World Health Organization (WHO) Strategic Advisory Group of Experts (SAGE) Working Group on Vaccine Hesitancy’s conclusions and recommendations on the definition and scope of vaccine hesitancy, the attempts to develop and pilot indicators to measure vaccine hesitancy, and potential strategies to address this issue (Hickler, et al. 2015 and MacDonald 2015). These recommendations and conclusions were endorsed by the WHO Strategic Advisory Group of Experts on immunization in October 2014, including the proposed definition of vaccine hesitancy as the delay in acceptance or refusal of vaccines despite availability of vaccination services. Vaccine hesitancy is complex and context-specific, varying across time, place, and vaccines. It is influenced by factors such as complacency, convenience, and confidence.

• Blume, S. 2006. Anti-vaccination movements and their interpretations. Social Sciences and Medicine 62.3: 628–642.

  DOI: 10.1016/j.socscimed.2005.06.020

  Conceptualizes resistance to vaccination and presents their historical roots. Drawing on empirical data from the United Kingdom and the Netherlands, describes the claims, actions, and discourse of anti-vaccination groups and the way parents think about vaccines.

• Cooper, L. Z., H. J. Larson, and S. L. Katz. 2008. Protecting public trust in immunization. Pediatrics 122.1: 149–153.

  DOI: 10.1542/peds.2008-0987

  Discusses the rise in public concerns regarding vaccine safety in high-income countries, describing the multiple factors that have contributed to these concerns. Includes the interdependent issues of an evolving communications environment and shortfalls in structure and resources that constrain research on immunization safety (immunization-safety science).

• Dubé, E., C. Laberge, M. Guay, P. Bramadat, R. Roy, and J. A. Bettinger. 2013. Vaccine hesitancy: An overview. Human Vaccines & Immunotherapeutics 9.8: 1763–1773.

  DOI: 10.4161/hv.24657

  Provides an overview of the phenomenon of vaccine hesitancy. First, vaccine hesitancy is characterized, and the possible causes of the apparent increase in vaccine hesitancy in the developed world are described. Then the article examines the multiple determinants of individual decision making about vaccination.

• Hickler, B., S. Guirguis, and R. Obregon. 2015. Vaccine special issue on vaccine hesitancy. Vaccine 33.34: 4155–4156.

  DOI: 10.1016/j.vaccine.2015.04.034

  Describes the focus of the special issue of Vaccine on vaccine hesitancy. Presents the products, conclusions, and recommendations of the joint World Health Organization and UNICEF Strategic Advisory Group of Experts (SAGE) Working Group on vaccine hesitancy that are included in the issue.

• Larson, H. J., and W. S. Schulz. 2015. The state of vaccine confidence. London: Vaccine Confidence Project, London School of Hygiene & Tropical Medicine.

  Presents the work of the Vaccine Confidence Project led by Heidi Larson at the London School of Hygiene and Tropical Medicine. Analyzes a number of vaccine confidence issues and the paths to their resolution over the past decade, including polio eradication and beyond. Also presents options for monitoring and measuring public confidence to detect waning confidence early and identify issues of concern, and reports on strategies that have had positive impacts in engaging populations to build trust and confidence.

• Leask, J. 2011. Target the fence-sitters. Nature 473.7348: 443–445.

  DOI: 10.1038/473443a

  Describes the impact of vaccine scares on parental vaccination decisions. Proposes strategies that the government can use to enhance vaccine acceptance: reducing structural barriers limiting access to vaccination services, developing tailored communication strategies to reach the vaccine hesitant, and ensuring the support of health-care providers.

• Leask, J., H. W. Willaby, and J. Kaufman. 2014. The big picture in addressing vaccine hesitancy. Human Vaccines & Immunotherapeutics 10.9: 2600–2602.

  DOI: 10.4161/hv.29725

  Proposes five major tasks to tackle vaccine hesitancy, including greater government investment in the strategic direction, capacity building, research, and evaluation of hesitancy in order to meaningfully address vaccine hesitancy. Calls for good monitoring of trends in the prevalence of vaccine hesitancy. Community-level and provider-level solutions are also proposed.

• MacDonald, N. E. 2015. Vaccine hesitancy: Definition, scope and determinants. Vaccine 33.34: 4161–4164.

  DOI: 10.1016/j.vaccine.2015.04.036

  Presents the SAGE Working Group on Vaccine Hesitancy’s agreed definition of vaccine hesitancy and its scope. The Vaccine Hesitancy Determinants Matrix is discussed. According to this matrix, three categories of factors are influencing the behavioral decision to accept, delay, or refuse some or all vaccines: contextual, individual and groups, and vaccine/vaccination-specific influences. The “3Cs” model of vaccine hesitancy (confidence, complacency, and convenience) is also presented.

• Moulin, A. M. 1996. L’aventure de la vaccination. Paris: Fayard.

  Bringing together more than thirty specialists—physicians, biologists, immunologists, historians, and sociologists—Moulin presents the history of vaccination, from Jenner and the first vaccination programs against smallpox to the actual “vaccine confidence crisis.” Begins with a chapter from Moulin that gives a detailed synthesis of the nature and evolutions of vaccination as a sociological object of study.

• Omer, S. B., D. A. Salmon, W. A. Orenstein, P. deHart, and N. Halsey. 2009. Vaccine refusal, mandatory immunization, and the risks of vaccine-preventable diseases. New England Journal of Medicine 360.19: 1981–1988.

  DOI: 10.1056/NEJMsa0806477

  Explores the determinants of vaccine refusal and its impact on transmission of vaccine-preventable diseases. Using data from the United States, this article describes secular and geographical trends in vaccine refusal, the individual and community risks engendered by vaccine refusals, and the characteristics of the parents who refuse vaccines. The role of health-care providers to address vaccine refusal is also discussed.