  We investigated daily COVID-19 cases and deaths in the 337 lower tier local
authority regions in England and Wales to better understand how the disease
propagated over a 15-month period. Population density scaling models revealed
residual variance and skewness to be sensitive indicators of the dynamics of
propagation. Lockdowns and schools reopening triggered increased variance
indicative of outbreaks with local impact and country scale heterogeneity.
University reopening and December holidays triggered reduced variance
indicative of country scale homogenisation which reached a minimum in
mid-January 2021. Homogeneous propagation was associated with better
correspondence with normally distributed residuals while heterogeneous
propagation was more consistent with skewed models. Skewness varied from
strongly negative to strongly positive revealing an unappreciated feature of
community propagation. Hot spots and super-spreading events are well understood
descriptors of regional disease dynamics that would be expected to be
associated with positively skewed distributions. Positively skewed behaviour
was observed; however, negative skewness indicative of cold-spots and
super-isolation dominated for approximately 8 months during the period of
study. In contrast, death metrics showed near constant behaviour in scaling,
variance, and skewness metrics over the full period with rural regions
preferentially affected, an observation consistent with regional age
demographics in England and Wales. Regional positions relative to density
scaling laws were remarkably persistent after the first 5-9 days of the
available data set. The determinants of this persistent behaviour probably
precede the pandemic and remain unchanged.
