Keep calm and carry on vaccinating: Is anti-vaccination sentiment contributing to declining vaccine coverage in...

In England, coverage for childhood vaccines have decreased since 2012/13 in the context of an increasingly visible anti-vaccination discourse. We determined whether anti-vaccination sentiment is the likely cause of this decline in coverage.

Descriptive study triangulating a range of data sources (vaccine coverage, cross-sectional survey of attitudes towards vaccination, UK-specific Twitter social media) and assessing them against the following Bradford Hill criteria: strength of association, consistency, specificity, temporality, biological gradient and coherence.

Strength of association: compared with well-documented vaccine scares, the decline in childhood vaccination seen since 2012/13 is 4-20 times smaller; consistency: while coverage for completed courses of the hexavalent and meningococcal vaccines decreased by 0.5-1.2 percentage points (pp) between 2017 and 2019, coverage for the first dose of these vaccines increased 0.5-0.7 pp; specificity: Since 2012-13, coverage decreased for some vaccines (hexavalent, MMR, HPV, shingles) and increased for others (MenACWY, Td/IPV, antenatal pertussis, influenza in 2 years of children), with no age-specific patterns. Temporality and biological gradient: the decline in vaccine coverage was preceded by an increase in vaccine confidence and a decrease in the proportion of parents encountering anti-vaccination materials. Coherence: attitudes towards vaccination expressed on Twitter in the UK became increasingly positive between 2017 and 2019 as vaccine coverage for childhood vaccines decreased.

In England, trends in vaccine coverage between 2012/13 and 2018/19 were not homogenous and varied in magnitude and direction according to vaccine, dose and region. In addition, confidence in vaccines increased during the same period. These findings are not compatible with anti-vaccination sentiment causing a decline in vaccine coverage In England.