# Global Estimates of COVID‐19 Morbidity and Mortality: A Cohort Study and Mathematical Model Analysis

## TL;DR

This study estimates the global impact of the COVID-19 pandemic using data from Qatar and a mathematical model, showing significant morbidity and mortality worldwide.

## Contribution

The study provides new global estimates of severe, critical, and fatal COVID-19 cases using a cohort study and mathematical modeling.

## Key findings

- The global incidence rate of severe, critical, or fatal COVID-19 was 1.13 per 1000 person-years.
- Fatal cases alone were estimated at 11.3 million globally.
- Most severe cases occurred during the pre-Omicron phase of the pandemic.

## Abstract

The true extent of the severity and fatality caused by the COVID‐19 pandemic remains uncertain. This study provides an approximate estimate of the global disease burden from the pandemic.

A cohort study followed the Qatari population from the onset of the pandemic to March 18, 2024, to estimate the age‐specific incidence rates of severe, critical, and fatal COVID‐19, classified according to World Health Organization criteria. A mathematical model then utilized these rates to generate regional and global estimates of COVID‐19 severity and fatality.

The incidence rate of any severe, critical, or fatal COVID‐19 throughout the pandemic was 1.13 (95% CI: 1.07–1.19) per 1000 person‐years, while that of fatal COVID‐19 alone was 0.11 (95% CI: 0.09–0.13) per 1000 person‐years. Globally, the number of severe, critical, or fatal COVID‐19 cases was estimated at 61.9 million (95% UI: 55.0–69.9 million), while the number of fatal COVID‐19 cases alone was estimated at 11.3 million (95% UI: 7.8–17.4 million). Both estimates showed large regional variations. Most severe, critical, and fatal COVID‐19 cases occurred during the pre‐Omicron phase of the pandemic.

The COVID‐19 pandemic had a profound global impact on morbidity and mortality, emphasizing the critical need for preparedness for future pandemics.