Heterogeneity in subnational mortality due to COVID-19: the case of Belgian districts

Benjamin-Samuel Schlüter, Louvain University (UCL)
Bruno Masquelier, Louvain University (UCL)

The COVID-19 pandemic has caused major mortality shocks in many countries. Yet few studies have evaluated the heterogeneity of the mortality shock at a sub-national level. First, we assess the change in subnational mortality levels’ heterogeneity in 2020 versus previous years. Then, we measure the shock of the pandemic using loss in life expectancy between the observed and projected districts life expectancy. We used the Chiang method to account for the uncertainty in life table computations at the district scale in 2020. We propose a method to project districts life expectancy in 2020. The Bayesian modelling approach makes it easy to combine the different sources of uncertainty in the shock assessment. This is of particular interest at a finer geographical scale characterized by high stochastic variation in annual death counts. Heterogeneity in the impact of the pandemic on all-cause mortality across districts is substantial, with some districts barely showing any impact whereas the Bruxelles-Capital and Mons districts show a decrease in life expectancy at birth of 2.5 (95\% CI: 1.9-3.1) and 2.3 (95\% CI: 1.3-3.4) years, respectively. Providing sub-national mortality estimates with their uncertainty is key to understand why certain areas have been hard hit in comparison to others.

Keywords: COVID-19, Bayesian methods / estimation, Mortality, Small area estimation

See paper.

  Presented in Session 186. Demographic Analysis of the Covid-19 Pandemic