在当今社会，突发急性传染病是影响人类生命健康的重大威胁，官方、专家或专业机构传播健康信息施以引导对于突发急性传染病防治至关重要，而作为亲历者的患者发布的相关信息及其作用也不容忽视，然而却少有研究对此进行探究。在短视频流行的背景下，本研究以抖音平台上新冠肺炎患者发布的自述视频为例，基于拓展平行反应模型，运用内容分析法考察其内容特征及其对公众在线参与和情绪唤起的影响。研究结果表明，所有视频均至少存在威胁（严重性、易感性）和效能（自我效能、回应效能）成分中的一种。威胁和效能成分均分别对视频点赞量、评论量和收藏量具有正向影响。同时，高严重性成分和高易感性成分分别促进公众的恐惧唤起和焦虑唤起，而高自我效能成分则显著减少公众的恐惧唤起和焦虑唤起，此外低回应效能成分促进公众的焦虑唤起。在此基础上，我们讨论了本研究的理论意义和现实价值。

In contemporary society, the emergence of acute infectious diseases poses a significant threat to human life and health. The dissemination of health information by officials, experts, or professional organizations is crucial for the prevention and control of such diseases. The information released by patients as witnesses and its role should not be ignored, but few studies have explored this. Against the backdrop of the popularity of short videos, this study examines self-reported videos by COVID-19 patients on the Douyin platform. Utilizing the Extended Parallel Process Model (EPPM), content analysis was conducted to explore the content features and their influence on public online engagement and emotional arousal. The findings reveal that all videos contained at least one component of threat (severity and susceptibility) or efficacy (self-efficacy and response efficacy). Both threat and efficacy components positively affected video likes, comments, and favorites. Meanwhile, the high severity component and the high susceptibility component were associated with the arousal of fear and anxiety respectively, while the high self-efficacy component significantly reduced these negative emotional responses. Additionally, the low response efficacy component was found to enhance anxiety arousal. On this basis, we discuss the theoretical significance and practical value of this study.