  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
\emph{virulence matrices} to study the evolution of COVID-19 cases and deaths
on a global scale. Finally, we introduce \emph{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.
