Factual Messaging and Clinician Voices Key to Vaccine Social Media Engagement

As health systems and public health agencies increasingly rely on digital platforms to promote vaccination, new research highlights that the effectiveness of these efforts depends heavily on message design. A recent cross-sectional study published in JAMA Network Open found that social media users are more likely to engage with vaccine-related posts that are factual, come from trusted public health organizations, and feature health care professionals.¹

“The findings from this study will inform the design of a social media-based study on COVID-19 and influenza vaccination messaging in California, evaluating the association of such messaging with vaccine intentions and uptake,” wrote the researchers of the study. “We will also share our insights with key stakeholders to enhance public health messaging strategies. Assessing audience preferences prior to campaign design may improve engagement and strengthen vaccination-related knowledge.”

The study surveyed 243 adults to evaluate preferences for vaccination-related social media content. Participants compared paired posts that varied by attributes such as messenger, tone, source, and topic, selecting which they would be most likely to engage with through likes, shares, or comments.

Findings showed that the credibility of the source plays a central role in driving engagement. Posts attributed to public health organizations, such as the California Department of Public Health, were significantly more likely to be preferred (adjusted odds ratio [AOR], 1.80; 95% CI, 1.57-2.07), as were posts from academic institutions like the University of California San Francisco (AOR, 1.67; 95% CI, 1.21-2.29).

Messenger identity also influenced engagement. Posts featuring health care workers (AOR, 1.28; 95% CI, 1.12-1.47) or older adults (AOR, 1.48; 95% CI, 1.22-1.80) were more likely to resonate with participants.

Tone emerged as another key determinant. Although some campaigns have experimented with humor to increase reach, the study found that humorous posts were significantly less likely to be preferred (AOR, 0.45; 95% CI, 0.36-0.57). In contrast, factual and straightforward messaging was associated with higher engagement, particularly in the context of vaccine communication, where clarity and trust are paramount.

Topic relevance further shaped user preferences. Posts related to COVID-19 (AOR, 2.35; 95% CI, 1.95-2.87) and influenza (AOR, 1.78; 95% CI, 1.54-2.06) were more likely to be selected, reflecting sustained public interest in infectious diseases with ongoing health impacts. Although most participants reported preferring visual content such as images and short videos, the study found that artwork type itself did not significantly influence engagement.

These findings are consistent with prior literature emphasizing the importance of trust and transparency in vaccine communication. A study found that messages emphasizing vaccine effectiveness and safety—particularly when delivered by trusted sources—can significantly influence behavioral intentions to vaccinate.² At the same time, overly casual or humorous messaging may undermine perceived credibility, especially when addressing serious health topics.

As social media continues to play a central role in health communication—with nearly 94% of study participants reporting daily use¹—organizations must carefully consider how they craft and deliver vaccine messaging. Partnering with credible institutions, elevating clinician voices, and prioritizing clear, evidence-based communication may enhance both engagement and trust.

In an era where misinformation can spread rapidly online, optimizing the design of public health messages is not just a matter of marketing—it is a critical component of improving vaccine confidence and uptake.

“In this cross-sectional study of adults in California, participants preferred vaccination-related social media posts that were factual, sourced from public health organizations, and featured health care professionals or older adults,” wrote the researchers. “Posts focused on COVID-19 and influenza were more likely to be selected than general vaccination messages, while a humorous tone was less preferred. These findings illustrate how experimental preference-based methods can inform the design of digital public health messaging.”

References

1. Miguel LA, Comfort AB, Riley AR, et al. Preferences for social media vaccination messaging. JAMA Netw Open. 2026;9(3):e262284. doi:10.1001/jamanetworkopen.2026.2284

2. Kerr JR, Freeman ALJ, Marteau TM, van der Linden S. Effect of information about COVID-19 vaccine effectiveness and side effects on behavioural intentions: two online experiments. Nat Hum Behav. 2021;5(5):600-609. doi:10.1038/s41562-021-01079-0