Disruptions resulting from an epidemic might often appear to amount to chaos but, in reality, can be understood in a systematic way through the lens of "epidemic psychology". According to Philip Strong, the founder of the sociological study of epidemic infectious diseases, not only is an epidemic biological; there is also the potential for three psycho-social epidemics: of fear, moralization, and action. This work empirically tests Strong's model at scale by studying the use of language of 122M tweets related to the COVID-19 pandemic posted in the U.S. during the whole year of 2020. On Twitter, we identified three distinct phases. Each of them is characterized by different regimes of the three psycho-social epidemics. In the refusal phase, users refused to accept reality despite the increasing number of deaths in other countries. In the anger phase (started after the announcement of the first death in the country), users' fear translated into anger about the looming feeling that things were about to change. Finally, in the acceptance phase, which began after the authorities imposed physical-distancing measures, users settled into a "new normal" for their daily activities. Overall, refusal of accepting reality gradually died off as the year went on, while acceptance increasingly took hold. During 2020, as cases surged in waves, so did anger, re-emerging cyclically at each wave. Our real-time operationalization of Strong's model is designed in a way that makes it possible to embed epidemic psychology into real-time models (e.g., epidemiological and mobility models).

翻译：流行性传染病的社会学研究的创始人Philip Stront认为, 流行性传染病的社会学研究的创始人Philip Stront认为,这不仅是一种流行病的生物学;还有可能出现三种心理社会流行病:恐惧、道德化和行动。 这项工作从经验上检验了强性模式,研究了2020年全年美国发布的与COVID-19大流行有关的122MTwitter语言的使用。我们在Twitter上确定了三个截然不同的阶段。每个阶段都有三种心理社会流行病的不同制度。在拒绝阶段,用户拒绝接受现实,尽管其他国家死亡人数在不断增加。在愤怒阶段(该国首次死亡之后开始),用户的恐惧转化为对即将发生改变的预感的愤怒。最后,在接受阶段,在当局实施物理调整措施之后,用户们在“新常态”上找到了三个不同的阶段。在拒绝阶段里,我们逐渐接受现实性波动的情绪在2020年不断上升,而我们接受的情绪在不断上升,在不断上升的时期里,在不断上升,在不断上升的时期,我们接受现实的情绪在不断上升。