Covid-19 vaccines saved almost 20 million lives worldwide during the first year they were rolled out, according to a mathematical modeling study published in the Lancet Infectious Diseases on Thursday, which found vaccines cut the potential global death toll from the coronavirus in half during that year.
Vaccines prevented 19.8 million out of a potential 31.4 million deaths during the first year after vaccines were first introduced in December 2020 to December 2021, according to the study, which reviewed Covid death records and excess death data from 185 countries and territories.
Vaccines saved the most lives in high and upper-middle income countries, where researchers estimated increased access to vaccines prevented 12.1 million deaths.
The study shows the “remarkable global impact” vaccination had on the pandemic, said Oliver Watson, lead author of the study and Schmidt science fellow at the Medical Research Council Centre for Global Infectious Disease Analysis at Imperial College London.
Almost 600,000 more deaths could have been avoided if the World Health Organization’s goal of vaccinating 40% of the population in every country by the end of 2021 had been achieved, researchers found.
While nearly 80% of deaths were avoided because of direct protection provided by vaccination, 4.3 million deaths were prevented due to indirect protection offered by others getting vaccinated, which led to a decrease in Covid transmission and reduced burden on healthcare systems, researchers found.
Several regional studies have estimated the number of lives saved by Covid vaccination, but the Lancet study is the first to quantify the impact of vaccines on a global level through modeling. A study from the Kaiser Family Foundation found almost a quarter of a million lives in the U.S. could have been prevented with more timely vaccination between June 2021 and April 2022. Researchers estimated that by December 2021, a year after the first vaccine was administered, around 55% of the global population had received at least one dose of a vaccine, while 45% had received two shots. Still, more than 3.5 million people have died from the coronavirus since vaccines first become available. Many more of these deaths could have been avoided if vaccines had been distributed more quickly around the world, researchers argued. The U.S. and other high-income countries aimed to donate 2 billion doses of vaccines to low- and middle-income countries by the end of 2021 through the COVID-19 Vaccines Global Access (COVAX) program. They ended up delivering just under half that amount. Researchers said vaccine distribution and delivery should be “scaled up” worldwide and efforts to fight misinformation should be ramped up to improve vaccine uptake to help prevent more Covid deaths.