Methods for estimating the excess mortality associated with the COVID-19 pandemic

Overview

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

While aggregate COVID-19 case and death numbers are being reported to WHO, they do not always provide a complete picture of the health burden attributable to COVID-19. In general, reported death numbers under-estimate the number of lives lost due to the pandemic, there are several reasons for this. They miss those who died without testing, they are contingent on the country correctly defining COVID as the cause-of-death and they miss the increases in other deaths that are related to the pandemic leading to overwhelmed health systems or patients avoiding care. A few countries have experienced lower than expected total deaths during the pandemic due to reduced contact and reduced mobility, which have led to reduced infectious disease related mortality as well as reduced transport and injury related fatalities. Reported COVID-19 death numbers do not account for this.

In light of the challenges posed by using reported data on COVID-19 cases and deaths, 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 details of the updated methodology applied to produce the estimates of excess deaths associated with the COVID-19 pandemic for a 24-month period (January 2020 to December 2021) at global, regional and national levels.