BACKGROUND:
Misinformation on social media during disasters is increasingly recognised as a major threat to effective emergency response, amplifying fear, eroding trust, and misdirecting resources. Despite growing attention to this issue, limited research has examined how public health professionals, key actors in risk communication, experience and manage misinformation in disaster contexts. Understanding these perspectives is essential for strengthening preparedness, communication strategies, and disaster resilience.

METHODS:
A cross-sectional online survey was conducted among public health professionals recruited through the European Public Health Conference and European Public Health Association networks. Participation was voluntary and anonymous. The survey examined exposure to misinformation during disasters, types and sources of misleading information, perceived operational impacts, and mitigation strategies. Quantitative data were analysed using descriptive statistics, and open-text responses were analysed using inductive qualitative synthesis.

RESULTS:
Ninety-two public health professionals participated. Overall, 91.5% identified social media misinformation as a significant operational barrier during disaster response. Facebook, WhatsApp, Instagram, YouTube, and X (Twitter) were most frequently cited, indicating a cross-platform challenge. Conspiracy theories were the most common form of misinformation, followed by rumours and politically framed content. Reported impacts included erosion of trust in official communications, increased unsafe behaviours, heightened public fear and anxiety, and diversion of emergency resources. Participants described mitigation strategies such as informal monitoring, ad hoc fact-checking, collaboration with trusted community figures, staff training, and public awareness campaigns. However, respondents consistently highlighted the lack of coordinated, system-level responses, emphasising the need for independent oversight mechanisms and real-time misinformation detection tools.

CONCLUSIONS:
Social media misinformation is perceived by public health professionals as a major operational barrier during disasters, undermining both community behaviour and response effectiveness. Findings highlight the need to integrate misinformation management into disaster preparedness frameworks, alongside coordinated governance, digital literacy initiatives, and structural interventions to strengthen public trust and resilience.