Methodology for estimating global excess deaths associated with COVID-19

Overview

The World Health Organisation (WHO) has been tracking the impact of COVID-19 as the pandemic has evolved over time.

Aggregate case and death numbers are being reported to the WHO and the data have been made publicly available. These data do not always provide a complete picture of the health burden attributable to COVID-19 nor of how many lives have been lost due to the pandemic, and there are a number of reasons for this. Some deaths that are attributable to COVID-19 have not been certified as such because tests had not been conducted prior to death. There have also been variations in the death certification rules countries have applied in the presence of comorbidities and COVID-19.

Beyond the deaths directly attributable to it are those that can be linked to the conditions that have prevailed since the pandemic began and have led to some health systems being overwhelmed or some patients avoiding healthcare. In light of the challenges posed by using reported COVID-19 data, excess mortality is considered a more objective and comparable measure that accounts for both the direct and indirect impacts of the pandemic. This document provides the methodology applied to produce the estimates of global excess deaths associated with COVID-19.