WHO, Gavi campaign delivers 100 million vaccine doses to children worldwide

More than 100 million vaccine doses reached children in 36 countries under a global catch-up drive that aimed to pull millions of young children back into routine immunization after pandemic-era setbacks. The Big Catch-Up delivered those doses to an estimated 18.3 million children ages 1 to 5, including about 12.3 million who had never received a single vaccine and roughly 15 million who had not previously been given a measles shot.

The World Health Organization and Gavi said the campaign concluded on 31 March 2026 after running across Africa and Asia, where the agencies said about 60% of the world’s zero-dose children live. The initiative also delivered 23 million doses of inactivated polio vaccine to un- and under-vaccinated children, a reminder that the effort was about more than one virus or one missed appointment. It was a race to restore routine protection before children aged out of the period when vaccines have the greatest effect.

The numbers mark a significant recovery effort, but they also show how deep the immunization gap remains. WHO says the program is forecast to meet its target of reaching at least 21 million un- and under-immunized children, yet UNICEF reported in July 2025 that 14.3 million infants were still zero-dose children in 2024 and nearly 20 million infants missed at least one dose of diphtheria, tetanus and pertussis vaccine. Globally, 89% of infants received at least one DTP-containing dose in 2024, and 85% completed the three-dose series, suggesting steady coverage rather than a full rebound.

The campaign was launched on 24 April 2023 by WHO, UNICEF, Gavi, the Bill & Melinda Gates Foundation and Immunization Agenda 2030 after WHO and UNICEF said essential immunization had fallen in more than 100 countries. At that time, more than 25 million children had missed at least one vaccination in 2021, with clinic closures, strained health systems, disrupted supply chains, conflict, climate shocks and vaccine hesitancy all widening the gaps. The Big Catch-Up’s close offers a rare measurable success in global public health, but the underlying crisis remains: millions of children in fragile and underserved communities are still being missed before preventable disease finds them.