Mapping the global opinion space to explain anti‑vaccine attraction

Vaccines save millions of lives every year. They are recommended by experts, trusted by the majority  of people, and promoted by expensive health campaigns. Even so, people with neutral attitudes are  more persuaded by people holding anti-vaccine than pro-vaccine attitudes. Our analysis of vaccine?related attitudes in more than 140 countries makes sense of this paradox by including approaches  from social infuence. Specifcally, we show that neutral people are positioned closer to anti- than to  pro-vaccine people in the opinion space, and therefore more persuadable by them. We use dynamic  social simulations seeded with vaccine survey data, to show how this efect results in a drift towards  anti-vaccine opinions. Linking this analysis to data from two other multi-country datasets, we found  that countries in which the pro-vaccine people are less associated to the neutrals (and so less able  to infuence them) exhibit lower vaccination rates and stronger increase in distrust. We conclude  our paper by showing how taking social infuence into account in vaccine-related policy-making can  possibly reduce waves of distrust towards vaccination.