Abstract
Vaccination is one of the most successful and cost-effective interventions designed by science which has helped in preventing millions of deaths, especially in children. The Expanded Programme on Immunization (EPI) was established by World Health Organization (WHO) in 1974 to develop immunization programmes throughout the world with polio, measles, diphtheria, tetanus, tuberculosis and whooping cough. The WHO South-East Asia Region (SEAR) has a disproportionately high burden of infectious diseases and has greatly benefitted from the EPI as compared to other regions with more than 90 per cent of the population having access to vaccines. The story of vaccines in South-East Asia is a testament to scientific progress, global collaboration, and unwavering commitment to public health. This article aims to discuss the journey of EPI in the WHO SEAR.