Global Vaccine Impact: Saving Millions, Addressing Risks, and Promoting Immunity Worldwide

Global immunization efforts have saved an estimated 154 million lives over the past 50 years, according to a landmark study published by The Lancet and led by the World Health Organization (WHO).

The study reveals that vaccination against 14 diseases — including 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.

Of the lives saved through immunization, 101 million were those of infants, making it the single greatest contribution of any health intervention to ensuring children survive their first birthdays and lead healthy lives into adulthood.

Measles vaccination alone accounted for 60% of the lives saved due to immunization, underscoring its outsized impact on reducing child mortality.

For each life saved through immunization, an average of 66 years of full health were gained, resulting in a total of 10.2 billion full health years gained over the five decades.

WHO Director-General Dr Tedros Adhanom Ghebreyesus emphasized that vaccines are among the most powerful inventions in history, noting that smallpox has been eradicated, polio is on the brink of eradication, and newer vaccines against diseases like malaria and cervical cancer continue to expand the frontiers of disease prevention.

The study highlights the critical role of immunization in primary health care, calling it an indisputable human right and one of the best investments in global health, while also underscoring its importance in preventing outbreaks, strengthening health security, and combating antimicrobial resistance.

Despite these gains, recent data shows setbacks: in 2024, the routine first dose of measles vaccine was missed by 20.6 million children worldwide — a significant increase from the 19.3 million who missed it in 2019 — revealing vulnerabilities exposed by the high transmissibility of measles and the lingering effects of the COVID-19 pandemic on health systems.

Ongoing efforts to recover, strengthen, and catch up on immunization coverage remain essential to sustaining progress and protecting populations from vaccine-preventable diseases.