Background: In recent years, influenza has become a severe disease and pandemic threat. There are more than 290,000 to 650,000 influenza-related deaths globally each year. Influenza vaccination is the best way to prevent influenza and potentially serious influenza-related complications. The current study aims to examine the effectiveness of fear-induced health campaigns on social media in promoting influenza vaccination with the focus on different sources. Methods: A 2 × 3 × 2 (visible source × receiver source × technological source) factorial online experiment was designed to investigate the effectiveness of fear appeal messages offered by different sources on social media. A total of 534 college students were recruited to participate in the experiment. Results: Individuals who receive messages from a verified visible source have greater intention to perform flu vaccination and seek flu-related information than those who acquire messages from an unverified one. Besides, visible source, receiver source, and technological source interact to affect flu-related information seeking. Conclusions: In addition to the message itself, different levels of message sources on social media should be considered for e-health campaign design, especially visible sources.
Keywords: e-health campaign; fear appeal; influenza; social media; source; telemedicine.