Sentiments in the Online Anti- and Pro-Vaccination Discourse on Twitter

Abstract

Vaccine hesitancy, which is a term to describe that people have doubts about vaccination and choose to delay or refuse vaccine uptake even though vaccines are readily available, is one of the greatest threats to global health. To effectively promote vaccine uptake and to tackle vaccine hesitancy it is important to gain insight into the vaccination discourse to get a better understanding of why people refuse vaccination. This study aims to examine the sentiments that are expressed in the online vaccination discourse and to research the differences in sentiments between the pro-vaccination majority and the anti-vaccination movement. Dutchlanguage vaccination-related messages were collected from Twitter ranging from January 2012 until June 2019 and categorised which resulted in 57 anti-vaccination tweets and 354 pro-vaccination tweets. A sentiment analysis and qualitative content analysis was conducted. Both anti- and pro-vaccination tweets contained strong subjectivity and polarity scores, thus tweets on both sides of the discourse were strong in sentiment and no meaningful difference was found. Anti- and provaccination adherents both used more negative feelings than positive feeling words in their tweets. The sentiments in both anti- and pro-vaccination tweets related to a strong sense of in-group identity. Sentiments expressed in tweets posted by anti-vaccination adherents related to the presence of reactance. These findings increase insight into the relevance of social identity and reactance in the decision-making of anti-vaccination adherents and suggest that more attention should be paid to the vaccination discourse on social media platforms such as Twitter. More insight into the online vaccination discourse could improve the understanding of how vaccine hesitancy develops and spreads which is needed to effectively counter vaccine hesitancy