ABSTRACT
Introduction: The debate on the Covid-19 vaccines has been very present on social networks since the very beginning of the health crisis, in a context of infodemics in which the presence of all kinds of information has been a breeding ground for misinformation or false news. Methodology: In this context, this article seeks to measure and characterise the conversation about Covid-19 vaccines on the social network Twitter. To this end, 62,045 tweets and 258,843 retweets from supporters and opponents of the vaccine were analysed between December 2020 and February 2021. Results: The start of the vaccination campaign was the turning point at which pro-vaccine discourse began to take precedence over anti-vaccine discourse. Antivaccine groups are characterised by being strongly cohesive clusters, with an appreciable level of activity, but with less capacity to viralise content. Conclusions and discussion: Anti-vaccine discourses tend to rely on alternative media or content shared on social networks, which corroborates that quality information is one of the main measures against disinformation. It also highlights the role of quality or legacy media and the desirability of further developing anti-disinformation policies specific to the type of digital conversation taking place on Twitter.