Understanding vaccine hesitancy: the evidence

Vaccination is an important public health intervention, but its effectiveness depends upon the uptake of vaccination reaching sufficient levels to yield 'herd' immunity. While the majority of the UK hold positive attitudes about vaccination, some people, including health professionals, decline vaccinations. This article reviews the evidence relating to vaccine hesitancy, its underlying factors and the sociodemographic variations. A second article will review the evidence relating to strategies to address vaccine hesitancy and promote vaccination acceptance.