Researchers estimate vaccines have saved 154 million lives over past half-century

An international team of health and medical researchers including workers at the WHO, working with economists and modeling specialists, has found that the use of vaccines to prevent or treat disease has saved the lives of approximately 154 million people over the past half-century.

In their study, published in The Lancet, the group used mathematical and statistical modeling to develop estimates for lives saved due to vaccines and then added them together to find the total.

The goal of the team was to evaluate the degree of success of the Expanded Program on Immunization (EPI) launched by the World Health Organization in 1974. The goal of the EPI has been to vaccinate all the children in the world against the most common deadly diseases. At its onset, the list included seven diseases; it has since been expanded to include 14.

As part of that effort, research has been conducted to develop vaccines, test them and then to use them once they have been declared both safe and effective. Since its inception, the EPI program has led to the development of many vaccines and the vaccination of millions of people, preventing suffering and death.

In this new effort, the research team sought to find out how successful the program has been. The work involved collecting and analyzing data at the local, regional and global levels. As part of that effort, they created 22 models based on 50 years of vaccination data for people around the world. The team then used the models to estimate lives saved and found the total to be approximately 154 million since 1974.

The research team also found that children benefited the most from vaccination—101 million of the lives saved were under the age of 1. They also found evidence that vaccination programs had a major impact on infant mortality rates—over the past half-century, rates have declined globally by 40%. The researchers also found that the measles vaccine made the biggest impact—it was responsible for 60% of the lives saved.

 Andrew J Shattock et al, Contribution of vaccination to improved survival and health: modelling 50 years of the Expanded Programme on Immunization, The Lancet (2024). DOI: 10.1016/S0140-6736(24)00850-X