Spatial distribution and determinants of childhood vaccination refusal in the United States

TL;DR

This study analyzes county-level childhood vaccine refusal in the US from 2012-2015, identifying social and political factors influencing refusal and spatial clustering to inform targeted public health strategies.

Contribution

It introduces a Bayesian zero-inflated negative binomial model to analyze fine-scale socio-demographic factors associated with vaccine refusal across US counties.

Findings

Spatial clustering of vaccine refusal explained by socio-demographic factors

Identification of social and political determinants linked to refusal

Potential to inform targeted vaccination campaigns

Abstract

Parental refusal and delay of childhood vaccination has increased in recent years in the United States. This phenomenon challenges maintenance of herd immunity and increases the risk of outbreaks of vaccine-preventable diseases. We examine US county-level vaccine refusal for patients under five years of age collected during the period 2012--2015 from an administrative healthcare dataset. We model these data with a Bayesian zero-inflated negative binomial regression model to capture social and political processes that are associated with vaccine refusal, as well as factors that affect our measurement of vaccine refusal.Our work highlights fine-scale socio-demographic characteristics associated with vaccine refusal nationally, finds that spatial clustering in refusal can be explained by such factors, and has the potential to aid in the development of targeted public health strategies for optimizing vaccine uptake.