The vaccine confidence gap The recent Decade of Vaccines Global Vaccine Action Plan(GVAP)  includes the strategic objective that:
“Individuals and companies should understand the value of vaccines, and demand immunization as both their right and responsibility”.
This was express recognition by the GVAP of the importance of addressing at a global level the so-called “vaccine confidence gap”. Acceptance of vaccination is an important but often forgotten element of vaccination uptake. Yet lack of confidence in and acceptance of vaccination remains a significant public health challenge; it has led to recent measles outbreaks across Europe, and polio resurgence in Nigeria. The second of five goals of the Decade of Vaccines is to “meet vaccination coverage targets in every region, country and community” . To measure success, the GVAP tentatively proposes two indicators:
1. Percentage of countries that have assessed (or measured) confidence in vaccination at subnational level
2. Percentage of un- and under-vaccinated in whom lack of confidence was a factor that influenced their decision
Measuring the problem. You cannot understand and change what you cannot measure (we say that a lot). We need standardised indices that allow us to measure & track key determinants of uptake & actual uptake. These must enable monitoring over time, as relative changes are likely to give more actionable information than absolute scores. Actual vaccination uptake can be hard to measure, and it may be necessary to record self-reported behaviours where possible to complement official data. The best proxy of behaviour is probably stated intention. A robust, psychometrically validated instrument could enable measurement and tracking of attitudes, intentions and self-reported behaviours (uptake). Importantly, such a tool could also identify social, psychological and demographic predictors of behaviour change which could be used to inform and tailor social and behavioural change interventions at a country or even community level. We are currently developing such an attitudinal barometer for adult vaccination in collaboration with Imperial College (who have already tested an instrument for parental attitudes to MMR) and will discuss this further soon.
However, this approach highlights a cardinal challenge to vaccination uptake – the definition of the problem must be measurable. People are variously looking at whether it is about refusal, hesitancy, confidence, trust or acceptance, and this seems often to lead to rather circular discussions. We propose that acceptance may be the best definition because it gives both a positive slant to the challenge and is potentially measurable. Acceptance could be defined as:
‘The intention to get vaccinated where there is access to, and awareness of, an affordable vaccine.’
While this will certainly not capture all the dimensions that may affect vaccination acceptance, it is a potentially measurable definition that may at least be an indicator.
Listen, understand, engage. It is also now possible to track and measure the conversation around vaccination in the mainstream and social media. This approach is increasing being used by companies to monitor the conversation around their products, services and brand. For example, Nestle has a (rather unfortunately named) ‘War Room’in which a team sits in front of 12 big screens and tracks mentions and discussions of their products in social media 24/7, responding to the public, and informing their marketing strategies in near real-time. We are currently testing a monitoring system (social barometer) that is fed by both passive monitoring of media and active (event-based) reporting from the HealthMap system. We envisage a simple dashboard that may be used by vaccination program managers to listen to discussions of their vaccines and programs at a local level, and perhaps to help them engage actively in the public discussion to build and sustain trust in their programs. Conceivably it may be possible to develop a composite index of vaccination uptake (official & self-reported), acceptance, intention to vaccinate, and pressure and temperature (volume and sentiment) of online discussions. Which again would only be an indicator, but may facilitate better tracking (in real time) of the mood around vaccination within a country or region, which is the first step in the Listen-Understand-Engage cycle of good vaccination advocacy.
Refs 1. WHO. Global vaccine action plan 2011-2020. Available at: http://www.dovcollaboration.org/wp-content/uploads/2013/03/GlobalVaccineActionPlan_interactive.pdf 2. WHO. Weekly Epidemiological Record, No. 20. 2013, 88, 201-216.