Life expectancy across the world has decreased during the coronavirus pandemic, according to a study published by the University of Washington. The findings reveal that Covid-19 was the second leading cause of death in 2021, and that – on a global scale – human life expectancy fell by 1.6 years between 2019 and 2021.

In a study published in The Lancet on the global burden of disease, injury and risk factors, researchers from the Institute for Health Metrics and Evaluation (IHME) at the University of Washington in Seattle report that Covid-19 was the second leading cause of death in 2021 and the third leading cause in 2020. The study found that back in 2019, the most common causes of mortality in descending order, were coronary heart disease (which causes heart attacks), stroke, chronic obstructive pulmonary disease (COPD) and lower respiratory tract infections. However, the pandemic upset this order considerably.

Although there were clear regional differences in Covid-19-related mortality rates, with Southeast Asia, East Asia and Oceania showing the smallest reduction of 0.4 years in life expectancy while Latin America and the Caribbean experienced the largest reduction of 3.6 years.

Según un nuevo estudio de @TheLancet Argentina 🇦🇷 fue de los países con mejor desmpeño en la pandemia

Tuvo una disminución de la expectativa de vida de 0,8 años y un exceso de mortalidad por COVID de 0,85

(ambos datos son menores que los promedios globales y de Lat Am) pic.twitter.com/hDzCPyKKjN

— Jonatan Konfino (@JKonfino) April 2, 2024

The researchers found that overall life expectancy rose by 6.2 years between 1990 and 2021. According to the study, the global rise in life expectancy has been driven by a reduction in mortality due to intestinal infections such as those causing diarrhoea. This was responsible for a 1.1-year life expectancy increase over the period.

The second largest impact on life expectancy growth was due to the reduction in deaths from lower respiratory tract infections, which accounted for 0.9 years of life expectancy gained between 1990 and 2021,

the study claims. The researchers also cite a reduction in deaths from stroke and coronary heart disease as key factors.

The IHME study cited is based on mortality estimates for 288 causes of death in more than 200 countries and regions and draws on more than 56,000 data sources such as autopsies, censuses and cancer registries. Covid-19-related mortality estimates are derived from an analysis of excess deaths due to the coronavirus pandemic for the period January 1, 2020 to December 31, 2021. Overall, the study is based on the expertise of more than 11,000 staff in over 160 countries and territories.

Another study has found that by 2050, more than three quarters of countries will not have high enough fertility rates to sustain their population size over time. Moreover, this will be the case in 97 per cent of countries by 2100, according to current projections.

The researchers also predict significant changes in the patterns of live births, with the proportion of live births in low-income regions almost doubling from 18 per cent in 2021 to 35 per cent in 2100.