Mapping vaccine sentiment: analyzing spanish-language social media posts and survey-based public opinion (Preprint)

Abstract

The internet and social media have been considered useful platforms for obtaining health information. However, critical and erroneous content about vaccines on SM has been associated with vaccination delays and refusal.

To determine the profile of the population using social networks to obtain information about vaccines through a survey and to analyze the sentiments and opinions regarding vaccines in Spanish-language posts on the social network X, along with their geolocation.

A study was conducted using two methodologies: an observational study in the population of Spain aged 18 years or older, obtaining information through a self-completed electronic questionnaire in 2021, and a second study that analyzed Spanish posts gathered from 'X' between March and December 2021. Orange Data Mining was used to create a workflow for sentiment analysis of the posts. Location-based analysis was conducted by drawing upon self-defined user locations from X, entered into Microsoft PowerBI for analysis. Social network analysis was conducted to identify the nature of the five largest groups of users conversing about vaccinations in Spanish by drawing upon NodeXL Pro.

Among the 1,312 respondents in the survey, 85.7% stated that they were regular social networks users, and 66% reported having encountered antivaccine information on social networks. Among these, 24.3% experienced doubts about receiving recommended vaccines, and of those with doubts, 13.3% refused at least one vaccine proposed by a healthcare professional. A total of 479,734 Spanish posts on X were analyzed, and 54.44% (261,183 posts) were negative, 28.18% were neutral, and 17.37% were positive. Sentiment varied across regions: more negative posts appeared to derive from South America, with a mix in Europe and more positive posts in North America. Analysis of the topic words and key themes allowed the grouping of the predominant themes of the five study groups, which were: vaccination efforts during the COVID-19 pandemic (1), issues of vaccine theft and struggles in managing and securing the vaccine supply (2), campaigns in the State of Mexico (3), vaccination efforts for older adults (4), and the vaccination campaign in Colombia to combat COVID-19 (5).

High proportions of exposure to antivaccine content were reported by the respondents. Sentiment analysis and geolocation of posts on the social network X revealed a significant amount of negative Spanish posts, predominantly from South America. The thematic analysis of conversations on X proved to be a highly useful tool for understanding the population's opinions about vaccines.