Ahead of the 50th anniversary of the Expanded Programme on Immunization (EPI) to take place in May 2024,  The Lancet has released a study that global immunization efforts have saved an estimated 154 million lives – or the equivalent of 6 lives every minute of every year – over the past 50 years.

The major landmark study to be published by The Lancet reveals that the vast majority of lives saved – 101 million – were those of infants.

The study, led by the World Health Organization (WHO), shows that immunization is the single greatest contribution of any health intervention to ensuring babies not only see their first birthdays but continue leading healthy lives into adulthood.

Of the vaccines included in the study, the measles vaccination had the most significant impact on reducing infant mortality, accounting for 60% of the lives saved due to immunization. This vaccine will likely remain the top contributor to preventing deaths in the future.

Over the past 50 years, vaccination against 14 diseases (diphtheria, Haemophilus influenzae type B, hepatitis B, Japanese encephalitis, measles, meningitis A, pertussis, invasive pneumococcal disease, polio, rotavirus, rubella, tetanus, tuberculosis, and yellow fever) has directly contributed to reducing infant deaths by 40% globally, and by more than 50% in the African Region.

WHO Director-General, Dr Tedros Adhanom Ghebreyesus, said “Vaccines are among the most powerful inventions in history, making once-feared diseases preventable,” 

“Thanks to vaccines, smallpox has been eradicated, polio is on the brink, and with the more recent development of vaccines against diseases like malaria and cervical cancer, we are pushing back the frontiers of disease. With continued research, investment and collaboration, we can save millions more lives today and in the next 50 years.”

The study found that for each life saved through immunization, an average of 66 years of full health were gained – with a total of 10.2 billion full health years gained over the five decades. As the result of vaccination against polio more than 20 million people are able to walk today who would otherwise have been paralysed, and the world is on the verge of eradicating polio, once and for all.

These gains in childhood survival highlight the importance of protecting immunization progress in every country of the world and accelerating efforts to reach the 67 million children who missed out on one or more vaccines during the pandemic years.

According to WHO, the study is the most comprehensive analysis of the programme’s global and regional health impact over the past five decades.

The study highlights that fewer than 5% of infants globally had access to routine immunization when EPI was launched. Today, 84% of infants are protected with 3 doses of the vaccine against diphtheria, tetanus and pertussis (DTP) – the global marker for immunization coverage.

Nearly 94 million of the estimated 154 million lives saved since 1974, were a result of protection by measles vaccines. Yet, there were still 33 million children who missed a measles vaccine dose in 2022: nearly 22 million missed their first dose and an additional 11 million missed their second dose.

Coverage of 95% or greater with 2 doses of measles-containing vaccine is needed to protect communities from outbreaks. Currently, the global coverage rate of the first dose of measles vaccine is 83% and the second dose is 74%, contributing to a very high number of outbreaks across the world.

Credit: WHO