Belgian COVID-19 Mortality, Excess Deaths, Number of Deaths per Million, and Infection Fatality Rates (9 March — 28 June 2020)

Background COVID-19 mortality and its relation to excess deaths, the number of Deaths Per Million (DPM), Infection Fatality Rates (IFRs) and Case Fatality Rates (CFRs) are constantly being reported and compared for a large number of countries globally. These measures may appear objective, however they should be interpreted with the necessary care. Objective Scrutiny of COVID-19 mortality in Belgium over the period 9 March – 28 June 2020 (Weeks 11–26), using the relation between COVID-19 mortality and excess death rates, the number of deaths per million, and infection fatality rates. Methods The relation between COVID-19 reported mortality and excess death rates is evaluated by comparing publicly available COVID-19 mortality (2020) and the difference of observed and predicted overall mortality. Predictions are based on weekly averages of historical overall mortality data in Belgium (2009–2019). Deaths per million are evaluated using demographic data of the Belgian population (2020). The infection fatality rate is estimated using a delay distribution between infection and death. The number of infections in Belgium is estimated by a stochastic compartmental model, which uses hospitalisation data, serial serological survey data, and COVID-19 mortality data (2020) for calibration. Results In Belgium, 9621 COVID-19 related deaths are reported between 9 March and 28 June 2020, which is close to the excess mortality estimated by weekly averages of historical mortality data (8985 deaths). This translates to 837 DPM and an IFR of 1.5% in the general population in Belgium. Both DPM and IFR increase with age and are substantially larger in the nursing home population. Conclusion Belgium has virtually no discrepancy between COVID-19 reported mortality and excess mortality. Due to this close agreement it is useful to consider the DPM and IFR, which are both age, sex, and nursing home population dependent. Data comparison of COVID-19 mortality between countries should rather be based on excess mortality than reported mortality. ### Competing Interest Statement All authors have completed the Unified Competing Interest form at [www.icmje.org/coi_disclosure.pdf][1] (available on request from the corresponding author) and declare that (1) PVD reports research grants from GSK Biologicals, Pfizer, SANOFI, Merck, Themis, Osivax, J&J and Abbott, grants from The Bill & Melinda Gates Foundation, PATH, Flemish Government, and European Union, outside the submitted work; (2) GM acts as advisor and member of International Data Monitoring Committees for several biopharmaceutical clinical trials, including for a COVID-19 vaccination trial of J and J; he receives research funding from GSK; (3) none of the other authors has anything to disclose. ### Funding Statement This project has received funding from the European Union's Horizon 2020 Research and Innovation Programma - Project EpiPose (No 101003688). The sero-prevalence study of which the results are used in this manuscript has been sponsored by the University of Antwerp's Research Fund. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: N/A All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes Data can be obtained from the authors upon reasonable request. [1]: http://www.icmje.org/coi_disclosure.pdf