Vaccines have prevented more than 2.5 million deaths caused by SARS-CoV-2, the virus behind COVID-19, according to a new study.
Led by researchers from the Catholic University of the Sacred Heart in Italy, the study found that one COVID-related death was avoided for every 5,400 vaccine doses administered.
About 82% of the lives saved involved people who were vaccinated before contracting the virus. Additionally, 57% of the total lives saved were during the Omicron period, and 90% of the deaths prevented were among individuals aged 60 and above.
Overall, the study estimated that vaccines saved 14.8 million years of life globally—equivalent to one year of life saved for every 900 doses administered. The findings were published in the JAMA Health Forum journal.
“Previous studies attempted to estimate lives saved by vaccines using different models, timeframes, or regional data,” said Dr. Angelo Maria Pezzullo and Dr. Antonio Cristiano. “However, this study is the most comprehensive to date. It uses global data, includes the Omicron period, quantifies life years saved, and is based on fewer assumptions regarding pandemic trends.”
For the analysis, researchers examined global population data and applied a series of statistical models to determine who became ill with COVID-19—either before or after vaccination—and during or after the Omicron period, including age and mortality outcomes.
“We compared this data with modeled estimates assuming no COVID vaccination. This allowed us to calculate how many people were saved and the number of life years gained due to vaccination,” explained Dr. Pezzullo.
The study also revealed that 76% of the saved life years were among people over 60. However, residents of long-term care facilities accounted for only 2% of the total benefit.
Children and adolescents accounted for just 0.01% of lives saved and 0.1% of life years saved. Similarly, young adults aged 20–29 contributed 0.07% of lives saved and 0.3% of life years saved, the researchers noted.
—IANS