Contagious content: the role of social media in vaccination.

Louise Fitzgerald, Emer Ryan

Keywords: Vaccine, Vaccination, Immunisation, Social Media


Social media is biggest development in information technology in the last decade. The internet and social media play a crucial role in dissemination of information (Zeng et al., 2010). Public health campaigns are slow to utilize these modern means of communication – although hashtags such as #VaccinesWork, featured during World Immunization Week 2019. The anti-vaccination movement has gained popularity over the last 40 years with a correlation with decrease in vaccination uptake (Ołpiński, 2012). A study co-authored by Broniatowski et al 2018 found that Russian trolls tweeted both pro vaccine and antivaccine messages in order to amplify the debate.

Research questions:

We conduct a content analysis of social media sites of vaccine relevant activity.


Vaccination related search terms, “vaccine” and “immunisation” and hashtags #vaccination and #immunisation were entered into the social media sites, Facebook, Instagram, Twitter and Pinterest. The 20 most popular posts, groups and pages were recorded and categorised into “vaccine information”, “pro-vaccination” and “anti-vaccination” subgroups. Snowball sampling was used to evaluate the most frequently used links and hashtags in each subgroup.


Term and hashtag “Immunisation” and #immunisation revealed much higher rates of pro-vaccination and vaccination information posts across all social media platforms than terms “vaccine” and hashtag #vaccine. Overall, groups with anti-vaccination manifestos were more common than pro-vaccination groups when all search terms were entered. Twitter had the highest number of anti-vaccination posts of the social media sites when search terms were used. In August 2019, Pinterest announced that searches on its site for vaccine-related topics will only turn up links to reputable public health organisations.


Traditional media fact-checked for their audience but that model has broken down with social media. We are facing a growing gap between where the scientific and official information lives and where the public is going.

Points for discussion:

We discuss impact of the internet and social networks on vaccination.

We discuss implications for online public health communications.

We discuss the need for future research including how best to combat bot-driven content.