From its approval in December 2020 and until December 2021, vaccines against covid-19 prevented the death of 19.8 million people of the 31.4 million potential deaths, according to the first study that has quantified its impact at scale world.
Most of these deaths (12.2 million of the 19.8) were averted in high- and upper-middle-income countries, stark evidence of the inequalities in access to vaccines around the world.
In fact, the study points out that another 599,300 deaths could have been avoided if the World Health Organization (WHO) goal of vaccinating 40% of the population of each country by the end of 2021 had been met.
Based on data from 185 countries, the study assesses deaths directly and indirectly prevented by covid-19 vaccines. The results are published this Friday in The Lancet Infectious Diseases.
Led by researchers from Imperial College London, the study has been funded by the Schmidt Futures and Rhodes Trust organizations, the World Health Organization, the UK Medical Research Council, the Bill and Melinda Gates Foundation, and the Community Jameel, among others.
The work concludes that the vaccines reduced by more than half the potential number of deaths during the pandemic in the first year (63%).
Of the almost 20 million deaths that have been prevented, almost 7.5 million were in the countries reached by the COVAX initiative, an alliance signed by 190 countries to guarantee equitable access to these medicines.
For Oliver Watson, lead author of the study and a researcher at Imperial College, these results show that vaccines "They have saved millions of lives. But more could have been done".
"If the targets set by the WHO had been achieved, we estimate that approximately 1 in 5 of the lives estimated to have been lost to covid in low-income countries could have been averted".
Until now, several studies have tried to estimate the impact of vaccination on the pandemic, but this is the first to be done worldwide.
The researchers used data on Covid deaths reported between December 8, 2020, and December 8, 2021, and accounted for underreporting of deaths in countries with weaker surveillance systems (China was not included due to its large size). population and its strict lockdown measures, which would have skewed the results).
The team found that over that period, vaccination averted approximately 19.8 million deaths out of the 31.4 million potential deaths that would have occurred.
In addition, it points out that 4.3 million deaths were avoided thanks to the indirect protection of vaccines that helped reduce the transmission of the virus and reduced the burden on health systems.
In general, the estimated number of deaths averted per person was higher in high-income countries, reflecting the earlier and broader rollout of vaccination campaigns in these areas.
The 83 countries included in the analysis and that resorted to the help of COVAX, avoided 7.4 million deaths out of a potential 17.9 million (41%).
But, it is estimated that failure to meet the COVAX goal of vaccinating 20% ​​of the population in each country has caused an additional 156,900 deaths (132,700 of them in Africa alone).
Similarly, failure to meet the WHO target of fully vaccinating 40% of the population in each country by the end of 2021 is estimated to have contributed to an additional 599,300 deaths worldwide that could have been prevented.
For Azra Ghani, from Imperial College London, this study highlights the need to guarantee fair access to the vaccines that go "beyond the simple donation".
And in a commentary published in the same journal, Alison Galvani, from Yale University (USA) stresses that "the saving of more than 19 million lives has been possible thanks to the unprecedented speed in the development and deployment of vaccines" which has been "an extraordinary global health feat".
However, he points out "Millions more lives could be saved with a more equitable distribution of vaccines".