Sarah Lane
Noni E. MacDonald
Melanie Marti
Laure Dumolard
Publication Date
March 28, 2018

Dalhousie University (Lane, MacDonald); World Health Organization, or WHO (Marti, Dumolard)

This analysis was undertaken to gather a global picture of hesitancy and whether this is changing over time. It reviews three years of data available as of June 2017 from the World Health Organization (WHO)/United Nations Children's Fund (UNICEF) Joint Report Form (JRF) to determine the reported rate of vaccine hesitancy across the globe, the cited reasons for hesitancy, if these varied by country income level and/or by WHO region, and whether these reasons were based upon assessment or opinion.

The WHO Strategic Advisory Group of Experts (SAGE)'s Working Group on Vaccine Hesitancy has defined two indicators to monitor vaccine hesitancy: (i) reasons for vaccine hesitancy, and (ii) percentage of countries that have assessed the level of hesitancy towards vaccination at the national or subnational level in the previous five years. These indicators were pilot tested and then introduced into the 2014 JRF and subsequently included in the 2015 and 2016 JRF. JRF response rates were calculated using all WHO Member States (194) for the denominator with the exception of the analysis of assessment rates in indicator 1 and 2 (regional and income-level analysis). The responses were categorised using the SAGE Working Group on Vaccine Hesitancy determinants matrix.

The number of countries that reported no hesitancy remained relatively consistent over the three ?years and overall was low; 2014 - 12 countries (6%), 2015 - 14 countries (7%), and 2016 - 14 (7%). The responses provided indicate that the SAGE vaccine hesitancy definition is well understood around the globe, which is reflective of the effort the SAGE Working Group put into developing a practical easily understood definition: the "delay in acceptance or refusal of vaccination 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".

Furthermore, the review provides evidence that the WHO determinants matrix is practical for categorising reasons cited for vaccine hesitancy, as over 95% of the cited reasons fit into a matrix determinant category. (Responses that did not fit were often due to their brevity. Potentially this problem could be addressed by encouraging more than one word answers to the JRF query.) The top three cited reasons for vaccine hesitancy globally in these three years were consistently: (1) risk-benefit (scientific evidence) (22%, 23%, 23%) e.g., "vaccine safety concerns", "fear of side effects"; (2) lack of knowledge and awareness of vaccination and its importance (15%, 13%, 10%) e.g., "lack of knowledge of parent on benefit of immunization"; and 3) religion, culture, gender, and socioeconomic issues regarding vaccines (10%, 9%, 12%) e.g., "due to certain religious sects (minority)", "traditional cultural beliefs". Of note, all matrix determinant categories except one (politics, policies) had at least one response assigned in the three years. The reasons for vaccine hesitancy varied by country income level and WHO region. In addition, the reasons for hesitancy did not necessarily remain static within a country over time, underlining not only the importance of assessments to determine if a common concern exists that can be addressed through a targeted national campaign but also the value of evaluation to assess if interventions have been effective.

According to the researchers, the trends and changes in the major category of reasons for hesitancy by country income level have implications for programmes aimed at helping to address hesitancy from WHO regional offices, UNICEF, international non-governmental organisations (NGOs), and partners. By 2016, in low-income countries, knowledge and awareness had dropped out of the top three category for vaccine hesitancy, and religion/culture/gender/socioeconomic had moved up. In lower-middle income countries, there was a shift; by 2016 knowledge/awareness had dropped from being the top category, and risk-benefit (scientific evidence) had become more prominent. "Evaluating trends over time will be helpful in assessing the effectiveness of both regional and individual country intervention efforts."

Countries reported that the reasons provided were predominately based upon opinion, as only 36% (50/141) in 2014, 39% (58/150) in 2015 and 38% (57/152) in 2016 noted these were based on an assessment. The number of countries that reported having completed an assessment related to vaccine hesitancy in the last five years stayed relatively consistent - and low - across the three years: 29% (56/194) in 2014, 36% (69/194) in 2015, and 33% (63/194) in 2016. Again, the rate of assessments varied across country income level - upper-middle-income countries were the least likely to have reported having done an assessment - and the six WHO regions. "It remains unclear why so few countries are carrying out assessments given their value for tailoring interventions to better address hesitancy both at the national level and in subgroups....Assessments are also key for determining if an intervention has been effective in reducing overall hesitancy....Is it a lack of survey tools in the language needed by the country? Lack of skills and resources to carry out an assessment? Lack of priority?" They continue: "when stakeholders are working with countries to address hesitancy and improve vaccine acceptance, if assessments are not available, it might be helpful to look at both regional trends as well as trends by country income level to determine what concerns might most effectively be targeted to help the country."

"Finally, the findings of this analysis provided some of the evidence for the 2017 Assessment Report of the Global Vaccine Action Plan recommendation that each country develop a strategy to increase acceptance and demand for vaccination, which should include ongoing community engagement and trust-building, active hesitancy prevention, regular national assessment of vaccine concerns, and crisis response planning."


Vaccine. 2018 Mar 28. pii: S0264-410X(18)30419-5.