New Research: COVID-19 Vaccines Saved 20 Million Lives Worldwide in the First Year

According to a new modeling study, published in The Lancet Infectious Diseases, COVID-19 vaccines are estimated to have prevented 20 million deaths worldwide in the first year of the vaccine program.

  • First modeling study to quantify the impact of COVID-19 vaccines on a global scale estimates that 19.8 million out of a potential 31.4 million deaths were prevented in the first year after vaccines were introduced (December 8, 2020 – December 8, 2021).
  • A further 599,300 deaths could have been averted if the World Health Organisation’s target of vaccinating 40% of the population in every country by the end of 2021 had been met.
  • High- and upper-middle-income countries accounted for the greatest number of prevented deaths (12.2 million/ 19.8 million), highlighting inequalities in access to vaccines around the world.
  • The study is based on data from 185 countries and territories and is the first to assess deaths averted directly and indirectly as a result of COVID-19 vaccination, using COVID-19 death records and total excess deaths from each country (or estimates where official data was not available). 

COVID-19 vaccines reduced the potential global death toll during the pandemic by more than half in the year following their implementation, according to estimates from a mathematical modeling study published on June 23, 2022, in The Lancet Infectious Diseases.

19.8 million out of a potential 31.4 million COVID-19 deaths were prevented worldwide in the first year of the vaccination program according to estimates based on excess deaths from 185 countries and territories.

The researchers estimate that a further 599,300 lives could have been saved if the World Health Organisation’s target of vaccinating 40% of the population in each country with two or more doses by the end of 2021 had been met.

Dr. Oliver Watson, lead author of the study, from Imperial College London, said: “Our findings offer the most complete assessment to date of the remarkable global impact that vaccination has had on the COVID-19 pandemic. Of the almost 20 million deaths estimated to have been prevented in the first year after vaccines were introduced, almost 7.5 million deaths were prevented in countries covered by the COVID-19 Vaccine Access initiative (COVAX). This initiative was set up because it was clear early on that global vaccine equity would be the only way out of the pandemic. Our findings show that millions of lives have likely been saved by making vaccines available to people everywhere, regardless of their wealth. However, more could have been done. If the targets set out by the WHO had been achieved, we estimate that roughly 1 in 5 of the estimated lives lost due to COVID-19 in low-income countries could have been prevented. ”

Since the first COVID-19 vaccine was administered outside of a clinical trial setting on December 8, 2020, almost two-thirds of the world’s population has received at least one dose of a COVID-19 vaccine (66%). The COVID-19 Vaccine Access initiative (COVAX) has facilitated access to affordable vaccines for lower-income countries to try to reduce inequalities, with an initial target of giving two vaccine doses to 20% of the population in countries covered by the commitment by the end of 2021. The World Health Organisation expanded this target by setting a global strategy to fully vaccinate 70% of the world’s population by mid-2022, with an interim target of vaccinating 40% of the population of all countries by the end of 2021.

Despite the incredible speed of the vaccine roll-out worldwide, more than 3.5 million COVID-19 deaths have been reported since the first vaccine was administered in December 2020.

Several studies have sought to estimate the impact of vaccination on the course of the pandemic. These studies have focused on specific regions, such as individual countries, states, or cities. The latest study is the first to estimate the impact of COVID-19 vaccinations on a global scale and the first to assess the number of deaths averted both directly and indirectly.

Mr. Gregory Barnsley, co-first author of the study, from Imperial College London, said: “Quantifying the impact that vaccination has made globally is challenging because access to vaccines varies between countries, as does our understanding of which COVID-19 variants have been circulating, with very limited genetic sequence data available for many countries. It is also not possible to directly measure how many deaths would have occurred without vaccinations. Mathematical modeling offers a useful tool for assessing alternative scenarios, which we can’t directly observe in real life.”

To estimate the impact of global vaccination programs, the researchers used an established model of COVID-19 transmission using country-level data for officially recorded COVID-19 deaths occurring between 8 December 2020 and 8 December 2021. To account for the under-reporting of deaths in countries with weaker surveillance systems, they carried out a separate analysis based on the number of excess deaths recorded above those that would have been expected during the same time period. Where official data was not available, the team used estimates of all-cause excess mortality. These analyses were compared with an alternative hypothetical scenario in which no vaccines were delivered.

The model accounted for variation in vaccination rates between countries, as well as differences in vaccine efficacy in each country based on the vaccine types known to have been predominately used in those areas. Notably, China was not included in the analysis owing to its large population and very strict lockdown measures, which would have skewed the findings.

The team found that, based on officially recorded COVID-19 deaths, an estimated 18.1 million deaths would have occurred during the study period if vaccinations had not been implemented. Of these, the model estimates that vaccination has prevented 14.4 million deaths, representing a global reduction of 79%. These findings do not account for the under-reporting of COVID-19 deaths, which is common in lower-income countries. The team did a further analysis based on total excess deaths during the same time period to account for this. They found that COVID-19 vaccination prevented an estimated 19.8 million deaths out of a total of 31.4 million potential deaths that would have occurred without vaccination, a reduction of 63%.

More than three quarters (79%, 15.5 million/ 19.8 million) of deaths averted were due to the direct protection against severe symptoms provided by vaccination, leading to lower mortality rates. The remaining 4.3 million averted deaths were estimated to have been prevented by indirect protection from reduced transmission of the virus in the population and reduced burden on healthcare systems, thereby improving access to medical care for those most in need.

Vaccine impact changed over time and in different areas of the world as the pandemic progressed, the study found. In the first half of 2021, the greatest number of deaths averted by vaccination was seen in lower middle-income countries, resulting from the significant epidemic wave in India as the Delta variant emerged. This subsequently shifted to the greatest impact being concentrated in higher income countries in the second half of 2021, as restrictions on travel and social mixing were eased in some areas leading to greater virus transmission.

Overall, the number of estimated deaths prevented per person was greatest in high-income countries, reflecting the earlier and wider rollout of vaccination campaigns in these areas (66 deaths prevented per 10,000 people in high-income countries vs 2.711 deaths prevented per 10,000 people in low-income countries). High- and upper-middle-income countries accounted for the greatest number of deaths averted (12.2 million/ 19.8 million), highlighting inequalities in access to vaccines around the world.

For the 83 countries included in the analysis that are covered by the COVAX commitment to affordable vaccines, an estimated 7.4 million deaths were averted out of a potential 17.9 million (41%). However, failure to meet the COVAX target of fully vaccinating 20% of the population in some countries is estimated to have resulted in an additional 156,900 deaths. Though this figure represents a small proportion of the total global deaths, these preventable deaths were concentrated in 31 African nations, where 132,700 deaths could have been averted if the target had been met.

Similarly, the shortfall in the WHO target of fully vaccinating 40% of the population of each country by the end of 2021 is estimated to have contributed to an additional 599,300 deaths worldwide that could have been prevented. Lower-middle income countries accounted for the majority of these deaths (347,500/599,300 [59.7%]). Regionally, most of these deaths were focused in the Africa and Eastern Mediterranean regions (348,900/599,300 [58.2%] and 126,800/599,300 [21.2%] respectively). If the 40% target had been met in all low-income countries, the number of deaths averted by vaccination in these areas would have more than doubled (200,000 additional deaths prevented on top of the 180,300 deaths estimated to have been averted under current vaccination rates).

Prof Azra Ghani, Chair in Infectious Disease Epidemiology at Imperial College London: “Our study demonstrates the enormous benefit that vaccines had in reducing deaths from COVID-19 globally. Whilst the intense focus on the pandemic has now shifted, it is important that we ensure the most vulnerable people in all parts of the world are protected from ongoing circulation of COVID-19 and from the other major diseases that continue to disproportionately affect the poorest. Ensuring fair access to vaccines is crucial, but requires more than just donating vaccines. Improvements in vaccine distribution and infrastructure, as well as coordinated efforts to combat vaccine misinformation and improve vaccine demand, are needed. Only then can we ensure that everyone has the opportunity to benefit from these life-saving technologies.”

The authors note several limitations to their findings. Notably, their model is based on a number of necessary assumptions, including the precise proportions of which vaccine types have been delivered, how they were delivered and the precise timing of when new virus variants arrived in each country. They also assumed that the relationship between age and the proportion of COVID-19 deaths occurring among infected individuals is the same for each country. More broadly, the findings from the study should be considered in the context of uncertainty in calculating the true death toll of the pandemic owing to the difference in country-level reporting of COVID-19 mortality.

Writing in a linked Comment, Professor Alison Galvani, who was not involved in the study, from Yale University School of Public Health, USA, said: “The saving of more than 19 million lives by the unprecedented rapidity of development and roll-out of COVID-19 vaccines is an extraordinary global health feat. Nonetheless, millions of additional lives could be saved by more equitable distribution of vaccines.”

She added: “High coverage in an individual country not only benefits that country but contributes to worldwide reduction in transmission and emergence of novel variants. An enduring collective response is both pragmatic and ethically imperative.”

Reference: “Global impact of the first year of COVID-19 vaccination: a mathematical modelling study” by Oliver J Watson, PhD; Gregory Barnsley, MSc; Jaspreet Toor, PhD; Alexandra B Hogan, PhD; Peter Winskill, PhD and Prof Azra C Ghani, PhD, 23 June 2022, The Lancet Infectious Diseases.
DOI: 10.1016/S1473-3099(22)00320-6

The study was carried out by researchers at the Medical Research Council Centre for Global Infectious Disease Analysis at Imperial College London, UK. It was funded by a Schmidt Science Fellowship in partnership with the Rhodes Trust, World Health Organisation, UK Medical Research Council, Gavi, Bill and Melinda Gates Foundation, National Institute for Health Research and Community Jameel.

[Editor’s Note: An earlier version of the headline incorrectly said “Saved 20 Million Deaths” instead of “Saved 20 Million Lives.”]

COVID-19Infectious DiseasesMortalityPopularThe LancetVaccine
Comments ( 11 )
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  • PETER R. GROVE

    A great deal of credit and a huge thank you needs to go to the ex-president who made this vaccine possible in less than a year. Pushing aside the bureaucracy and the red tape that strangles anything government does this president lead this nation through the pandemic and into a brighter future. Thank you President Trump!!!

    • Dr Rodriguez

      Absolutely!

      I can’t even imagine the disaster that would have ensued if Biden was president then.

  • Charles G. Shaver

    Personally monitoring US mortality for chronic disease reasons prior to Covid-19, based on 2017 statistics alone I knew almost immediately deaths reportedly due to Covid-19 were suspicious. Retrospectively, the total number of alleged Covid-19 US deaths is roughly what we could expect of medical errors (announced in May of 2016 by Johns Hopkins researchers to be the third leading cause of death in the US, behind only heart disease and cancer) in the same time frame, especially in consideration of population growth since 2017 and a mild 2021-2022 flu season. I postulate the truly accurate math in the study is best determined by following the money trail to those who funded it.

  • rassalas

    This is good? How is suspending Darwin’s laws of natural selection a good thing? Any true scientist would point out this makes us weaker.

    • What

      You do know that the immunity a vaccine provides isn’t passed down, right? Why would a vaccine have any bearing on the traits of an offspring? Or are you just trolling the comments section of an article with ignorance because you enjoy the negative reactions

  • Robin

    They can’t let things rest. They keep on trying to tear apart family and friends. 3 quarter’s of the world know the truth now. It was leaked from a lab in China. 4 scientists were paid off by good old Fauci. Read the news and see for yourself. The truth is being told. It is being reported by the media who care about our Country and the People in it. Believe me when I say their are news stations and reporters out in the world and the USA that still only report the truth. Just search and you will find one. That is if the truth is important & really matters to you. The election fruad claim mist be straightened out and proven to the citizens of our Country what the end results were. If it is not our Country will never come together and be one again. Then the rich will get richer. At least I’ll still have my dignatee and my pride.Those will never be taken away. I will be able to live with myself and the choices I made.Save your energy if you are thinking about messing with me with things that don’t matter right now.

    • Nope

      My mom is a chemo patient, and has both shots and the booster but still got COVID because her immune system isn’t strong enough from taking the chemo drug to trigger that response. She always masked and distanced, and never left the house except to buy food but she STILL got it and nearly died. All because somebody couldn’t be bothered to stay home when they were sick. I’m tired of people acting like they’re being oppressed because they’re asked to wear a mask or encouraged to get vaccinated. Those things could save somebody’s life. Unless you’ve been afraid your mom might die alone because you’re not allowed to see her, you don’t have any room to talk about being oppressed. Don’t believe conspiracy bullsh-tm

  • Tom

    Death payouts have gone up by 163% since the vaccines have been given, since 2021. That is apocalyptic. Vaxxines are killing way more people than covid. Just look up the numbers, it’s all there. Vaccines are slaughtering they population.

    • Nope

      If you don’t think the deaths are really from COVID than why don’t you visit your local hospital’s COVID ward without a mask. If you’re not vaxed you’ll be fine right?

  • Nope

    My mom is a chemo patient, and has both shots and the booster but still got COVID because her immune system isn’t strong enough from taking the chemo drug to trigger that response. She always masked and distanced, and never left the house except to buy food but she STILL got it and nearly died. All because somebody couldn’t be bothered to stay home when they were sick. I’m tired of people acting like they’re being oppressed because they’re asked to wear a mask or encouraged to get vaccinated. Those things could save somebody’s life. Unless you’ve been afraid your mom might die alone because you’re not allowed to see her, you don’t have any room to talk about being oppressed. Don’t believe conspiracy bull.

    • Nope

      If the deaths are part of a conspiracy and not COVID than it would be one of the largest in history, surely. Why would the US government use COVID to opress people, they don’t need an excuse. They’ve been doing it in plain sight since this country has been founded.