Nearly 20 million lives were saved by COVID-19 vaccines during their first year, but even more deaths could have been prevented if international targets for the shots had been met, researchers reported today.
On December 8, 2020, a retired shop assistant in England received the first injection in what would become a global vaccination campaign. Over the next 12 months, more than 4.3 billion people around the world queued for the vaccines.
The effort, though marred by lingering inequalities, prevented deaths on an unimaginable scale, said Oliver Watson of Imperial College London, who led the new modeling study.
“Catastrophic would be the first word that comes to mind,” Watson said of the outcome if vaccines had not been available to fight the coronavirus. The findings “quantify how much worse the pandemic could have been if we didn’t have these vaccines.”
The researchers used data from 185 countries to estimate that vaccines prevented 4.2 million COVID-19 deaths in India, 1.9 million in the United States, 1 million in Brazil, 631,000 in France and 507,000 in the United Kingdom.
According to the study published today in the journal Lancet Infectious Diseases, an additional 600,000 deaths would have been prevented if the World Health Organization’s target of 40% vaccination coverage by the end of 2021 had been met.
The main finding – 19.8 million COVID-19 deaths were prevented – is based on estimates of more deaths than usual during the period. With only reported COVID-19 deaths, the same model yielded 14.4 million deaths prevented by vaccines.
The London scientists excluded China due to uncertainty about the impact of the pandemic on deaths there and its huge population.
The study has other limitations. The researchers did not include how the virus would otherwise have mutated if there were no vaccines. And they didn’t consider how lockdowns or mask-wearing would have changed if vaccines weren’t available.
Another modeling group used a different approach to estimate that 16.3 million COVID-19 deaths were prevented by vaccines. That work, by the Institute for Health Metrics and Evaluation in Seattle, has not been published.
In the real world, people are more likely to wear masks as cases increase, said the institute’s Ali Mokdad, and the 2021 delta wave without vaccines would have triggered a major policy response.
“As scientists, we may not agree on the number, but we all agree that COVID vaccines have saved many lives,” Mokdad said.
The findings underscore both the achievements and shortcomings of the vaccination campaign, said Adam Finn of Bristol Medical School in England, who, like Mokdad, was not involved in the study.
“While we did pretty well this time — we’ve saved millions and millions of lives — we could have done better and should do better in the future,” Finn said.
Funding came from several groups, including the WHO; the UK Medical Research Council; Gavi, the Vaccine Alliance; and the Bill and Melinda Gates Foundation.