Understanding vaccine hesitancy: cognitive biases and the role of trust

Vaccines have been proven to be a safe and effective way to reduce the incidence of diseases, yet there is a growing number of individuals who perceive them as dangerous and view them with suspicion and distrust. This sentiment, called vaccine hesitancy, is causing diminishing vaccination rates in most Western countries. This article addresses the causes of vaccine hesitancy. In the first part, a description of its current state is canvassed; the second part discusses the role of different cognitive biases that may play a role in shaping doubts against vaccines, while the third part considers how much the role of trust toward doctors, public institutions, and the pharmaceutical industry contributes to those positions. In conclusion, a brief discussion of some potential counter-measures is provided.