ABSTRACT
The politicization of coronavirus disease 2019 (COVID-19) in the United States and abroad has received significant scholarly attention, particularly surrounding misinformation circulating on social media among millions of users. However there has been far less attention paid to how platforms like Facebook, Twitter, and others impact vaccine uptake within local, geographically specific communities. Local public health departments view platforms as critical communication infrastructure for outreach. Through a case study of Illinois, we examine how vaccine uptake is associated with county-level public health communication on Facebook, political regionalism, demographic variation, and digital access and reach. We ask about (a) discoverability: are individuals conducting digital searches able to find and access local public health information on their websites and social media? (b) reach: does growth in public health departments' Facebook followers correlate to vaccination rate? and (c) practices: is there an association between discoverability, moderation policies/practices of local public health departments' Facebook pages, and county-reported vaccination rates? We draw on original data about discoverability and local public health department's Facebook pages in addition to secondary data on voting behavior and rurality. We find discoverability as well as moderation are positively associated with vaccination rates, while greater Facebook reach in rural Illinois is negatively correlated with vaccination rates.