Background: The objective of this systematic review is to draw lessons from the prior studies for immunization, which can aid the development of interventions for vaccinations against COVID-19 and other contagious diseases. Our interests lie in large-scale public vaccination interventions. We aim to answer why few social media interventions have succeeded in increasing uptake rates despite the known affordances of social media in mobilizing crowds for causes. 

 

Methods: This review searched for seven databases in medicine, health, and social sciences to answer this question using three search terms (social media, vaccination, and interventions) and their variations. Articles included were from scholarly, peer-reviewed journals; written in English and were published from January 2010 to March 2021. We reviewed 92 papers in total. Moreover, we have developed a relational database organized by seven common attributes crucial for describing interventions (e.g., vaccine type, populations) and made this database available to the public.

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Results: Our analyses using this database show the disparities in interventions conducted across vaccine types, target populations, urbanicity, regions, and communication modalities. Most interventions focused on Human Papillomavirus vaccines, adolescents and young adults, urban areas, and reminder/recall. In addition, only 55 out of these 92 interventions (60%) reported statistically significant increases in the immunization rates. In addition, 50 out of 92 studies employed reminders and recalls, and only 16 studies used social media. Out of these 16 studies, only 1 study reported a significant increase in the uptake rates. As a potential reason for the low success rates, we note the absence of theories and methodology to measure the effectiveness of large-scale social media vaccination interventions. Lastly, we suggest that social media interventions should serve vaccinees’ particular predispositions towards vaccines (adherent, complacent, and hesitant) to increase success rates and seek collaborations with regional healthcare providers.