Heidi Larson’s group at the London School of Hygiene & Tropical Medicine just published a review in Vaccine that attempts to construct a descriptive model of parental vaccine hesitancy. They surveyed the literature on hesitancy from both developed and developing countries.
They adopt the term vaccine hesitancy in part because it’s less polarizing than the term anti-vaccine. It describes a continuum of attitudes about vaccine but also a continuum of practices around vaccination, or, as they say, those “in the middle of a continuum of total acceptors to complete refusers.” It’s a relatively new concept; in fact, only 6 of the 1,164 articles included in the review employed the term vaccine hesitancy. (I wonder if this definition leaves out a total acceptor, in terms of behavior, who still has doubts about vaccination.)
What’s so interesting about the paper is the way that it points out the sometimes seemingly conflicting nuances of promoters and barriers to vaccination. For example, in the US, both high and low income were barriers to vaccination (the latter not because of cost, but because of distrust of healthcare providers). In Nigeria, low income was a barrier because of low parental education and access to vaccines. However, in a different study, low income in Nigeria was identified as a promoter (the study from which this conclusion comes relates the promotion effect to positive local community influences).
Health knowledge influenced by conventional medical thinking promoted vaccination, but health knowledge influenced by myths, rumors, and alternative medicine concepts was a barrier (Nigeria, The Netherlands). In the US, conventional health knowledge was a promoter, but a mother’s plan to breastfeed was a barrier.
Somewhat surprisingly, different promoters and barriers may apply not just in different countries, and not just for different vaccines, but even for different doses of the same vaccine. The latter was evident in a British study of MMR vaccination, in which a perception of the social benefit of the vaccination was a promoter of the second dose of the vaccine, but not the first.
The authors point out the shortcomings of popular theories of health behavior to explain the complex factors related to vaccine hesitancy. They say that the Health Belief Model and the Theory of Planned Behavior, while they may be useful to explain individual influences on vaccination decisions, fail to address broader, contextual influences to vaccine hesitancy. It calls to my mind Julie Leask’s recent work applying the Transtheoretical Model to vaccination communication interactions with parents who are located on different parts of the hesitancy continuum.
The review looked only at studies of childhood vaccination up to age seven, and so we may be missing an understanding of vaccine hesitancy for adolescent vaccines. I hope they work on that next.
Image from The Historical Medical Library of The College of Physicians of Philadelphiaz: Final Report of the International Tuberculosis Campaign, July 1, 1948–June 30, 1951. Copenhagen: The International Tuberculosis Campaign, October, 1951.
Antai D. Gender inequities, relationship power, and childhood immunization uptake in Nigeria: A population-based cross-sectional study. Int J Infect Dis 2012;16:E136-45.
Brown K et al. Attitudinal and demographic predictors of measles-mumps-rubella vaccine (MMR) uptake during the UK Catch-Up Campaign 2008–09: Cross-sectional survey. PLoS One. 2011; 6(5): e19381. doi: 10.1371/journal.pone.0019381
Larson, HJ, Jarrett C, Eckensberger E, Smith DMD, Paterson P. Understanding vaccine hesitancy around vaccines and vaccination from a global perspective: A systematic review of published literature, 2007-2012. Vaccine. 32;19:2150-2159.
Leask J. Kinnersley P, Jackson C, Cheater F, Bedford H, Rowles G. Communicating with parents about vaccination: A framework for health professionals. BMC Pediatr. 2012;12:154. doi: 10.1186/1471-2431-12-154