突发事件爆发后网络舆情中往往产生若干热点，一些重要问题被大众忽视而形成舆情盲点。针对网络舆情热点存在局限性的问题，文章构建了突发事件情境下舆情盲点探测的方法，识别舆情发展中没有或较少得到关注的舆情盲点，从而使舆情向着更合理的方向发展，切实解决突发事件中产生的各种问题。以突发公共卫生事件为例，基于4R理论构建事件处置各阶段中应受到重视的关注点体系，获取石家庄疫情的舆情数据进行主题提取，通过比较关注点体系与舆情主题的差异来探测舆情盲点。研究发现在舆情的形成期建立预警系统、编制应急预案、定期培训属于舆情盲点。高潮期舆情盲点包括院内感染控制、物资监管、信息上报、防范境外输入、行政监督等。消散期舆情盲点包括完善法制、责任与奖惩、善后处置等。文章所提出的舆情盲点探测方法为网络舆情主题分布的科学性判断与干预策略提供量化的参考依据与方法，为事件处置提供有益借鉴。

After the outbreak of public emergencies, there are often several hot spots in the online public opinion. But some important issues are ignored by the public. Then blind spots of public opinion are formed. In view of the limitation of hot spots of online public opinion, this study constructs a blind spot detection method under the situation of public emergency, to identify the blind spots that are not or less paid attention to in the development of public opinion, and to make public opinion develop in a reasonable direction and effectively solve various problems arising from public emergencies. Taking a public health emergency as an example, this study constructs a focus system that should be paid attention to in each stage of emergency management based on the 4R theory. We obtained the microblog data of Shijiazhuang epidemic for topic extraction, and detected the blind spots by comparing the differences between the focus system and public opinion topics. It is found that in the forming period of public opinion, the establishment of early warning system, compiling emergency response plan, regular training are the blind spots. In the period of climax, topics such as nosocomial infection control, material supervision, information reporting, preventing imported cases and patient management are blind spots. For the disappearing period, topics such as perfecting legal system, reward and punishment, aftermath disposal are blind spots. The blind spot detection method of public opinion proposed in this paper provides a quantitative reference and the method for scientific judgment and intervention strategy of the topic distribution of online public opinion, and provides a useful reference for the disposal of public emergencies.