Social media use of health in videos prior to and post Covid-19: decoding anti-vaccine communication to prevent childhood vaccine hesitancy in Spain

Abstract

Vaccination is considered one of the most effective methods of disease prevention. However, parents’ vaccine hesitancy persists as a significant public health challenge. Spanish anti-vaccine videos on YouTube prior to COVID-19 have now moved onto Odysee. This study works with two 250 video samples, one from each platform.
Both searches were conducted using clean browsers, without user login, and surfing as a guest, to simulate the experience of the general public. Identical keywords and collection protocols were used to minimise selection bias. Quantitative content analysis was performed, focusing on the variation in communication techniques, source credibility, video format, channel type, and persuasiveness between the two periods. Comparative statistics and thematic analysis informed the findings.

We use identical search terms and a guest mode to simulate the general user experience to minimise algorithmic and selection bias. We focused on variations in communication techniques, credibility cues, video formats, channel types, and persuasive methods. Results show that, before COVID-19, anti-vaccine messages predominantly took the form of long public presentations delivered by professionals in alternative medicine and published by corporate channels. Post-pandemic content on Odysee increased in quantity, became shorter, and varied more in format (including interviews, documentaries, and video conferences) and was predominantly distributed by private individuals curating and cross-posting content. We found journalists as new presenters.

Health professionals may leverage these insights to counteract parents' vaccine hesitancy in Spain and identify persuasive triggers used in online disinformation. Future communication strategies to promote childhood immunisation should consider both content and messaging techniques.