This paper introduces new methods to study the changing dynamics of COVID-19 cases and deaths among the 50 worst-affected countries throughout 2020. First, we analyse the trajectories and turning points of rolling mortality rates to understand at which times the disease was most lethal. We demonstrate five characteristic classes of mortality rate trajectories and determine structural similarity in mortality trends over time. Next, we introduce a class of virulence matrices to study the evolution of COVID-19 cases and deaths on a global scale. Finally, we introduce three-way inconsistency analysis to determine anomalous countries with respect to three attributes: countries’ COVID-19 cases, deaths and human development indices. We demonstrate the most anomalous countries across these three measures are Pakistan, the United States and the United Arab Emirates.

本文介绍了研究 2020 年 50 个受影响最严重国家中 COVID-19 病例和死亡动态变化的新方法。首先，我们分析了滚动死亡率的轨迹和转折点，以了解该疾病在什么时候最致命. 我们展示了死亡率轨迹的五个特征类别，并确定了死亡率趋势随时间的结构相似性。接下来，我们引入一类毒力矩阵来研究全球范围内 COVID-19 病例和死亡的演变。最后，我们引入三向不一致性分析根据三个属性确定异常国家：国家的 COVID-19 病例、死亡和人类发展指数。我们展示了这三项措施中最反常的国家是巴基斯坦、美国和阿拉伯联合酋长国。