[COVID-19 and vaccination: analysis of public institution's role in information spread through Twitter.]

The COVID-19 pandemic has been a time where social media allows increased conversations about it. These conversations have spread various conspiracies about vaccines against COVID-19. It is, therefore, necessary to develop communication strategies, led by official accounts, that offer accessible information on vaccination as a preventive public health strategy. The aim of this study was to analyze the role of public institutions on Twitter campaign #yomevacuno to deal with misinformation about vaccination against COVID-19.

This paper performs a social network analysis and content analysis of Twitter data, using NodeXL software, from December 8^th to 23^rd, 2020. Tweets included content #yomevacuno hashtag.

A total of 6,080 interactions were collected, 82% were tweets. Data shows that public institutions generate 53.36% of traffic information, the most important was the Ministerio de Sanidad from Spain. Content analysis revealed that 48% of a sample of 50 Tweets the message was focused on vaccination as a social responsibility to defeat COVID-19 pandemic.

The communication strategy of #yomevacuno hashtag, has been led by the Ministerio de Sanidad of Spain, by comparison to other campaigns in which there was no large presence of public institutions. This case represents the importance of social media as a way to spread information and prevention, even in public health and the need for them to be led by public organizations rather than by individual users.