# Expanded Program on Immunization

The Expanded Programme on Immunization is a global health initiative launched by the World Health Organization in May 1974, with the aim to make vaccines available to all globally

## Introduction

Vaccination has been one of the most impactful public health interventions of the past century. Since the foundation of the Expanded Programme on Immunization (EPI) by the World Health Organization (WHO) in 1974, vaccines have provided the single greatest contribution to improving health outcomes globally, particularly among children and infants. Widespread immunization has substantially reduced the morbidity and mortality rates from diseases such as tuberculosis, poliomyelitis, measles, diphtheria, tetanus, pertussis, hepatitis B, yellow fever, meningitis A and many others. Recent innovations have expanded the impact of vaccines in addressing not only childhood diseases but also adult and emerging diseases, such as COVID-19.

## History
### Milestones in Global vaccination

| Year | Milestone | Description |
| 1974 | EPI launch | WHO established EPI in 1974 to protect children worldwide against diseases such as smallpox, measles, poliomyelitis, tuberculosis, diphtheria, tetanus, and pertussis by 1990. |
| 1979 | PAHO revolving fund | The Pan American Health Organization launched a fund to facilitate vaccine procurement |
| 1982 | UNICEF child survival and development revolution | UNICEF launched GOBI strategy which focused on growth monitoring, oral rehydration therapy, breastfeeding, and immunization |
| 1984 | EPI’s First standardized schedule | vaccination schedule was revised to include BCG, DTP, polio, and measles at specified ages |
| 1990 | Declaration of Manhattan, Children’s Vaccine Initiative | This Initiative aimed to accelerate vaccines development to enhance EPI performance |
| 1999 | Strategic Advisory Group of Experts (SAGE) on immunization | SAGE was established to advise WHO on global immunization policies, strategies, and research |
| 2000 | Gavi, The Vaccine Alliance | Was established to address market failure in certain countries and increase access to vaccines |
| 2000-present | Ongoing Acceleration of New Vaccine Introduction | Included initiatives like pneumococcal conjugate vaccines (PCV), rotavirus vaccines, and meningococcal A conjugate vaccine, malaria vaccine to expedite introduction |
| 2017 | Coalition for Epidemic Preparedness Innovations (CEPI) | CEPI was launched to as a response to Ebola, Zika, and SARS outbreaks to develop vaccines for emerging infectious diseases |
| 2020 | Immunization Agenda 2030 (IA2030) | IA2030 was setup to ensure universal access to vaccines, strengthen health care systems, and support universal health coverage. |
| 2020-2023 | COVID-19 Vaccines Global Access (COVAX) | Was established to accelerate the development, production, and equitable distribution of COVID-19 vaccines |
| 2023-2024 | The Big Catch-Up | This Initiative focuses on restoring immunization coverage to pre-COVID-19 levels and strengthen routine immunization systems to achieve 2030 targets |
| 2024 | EPI Expansion | EPI is expanded to cover vaccines against 13 global and 17 context-specific vaccine-preventable diseases |

## Impact of vaccination on global Health

Since the establishment of EPI in1974, vaccination has prevented 154 million deaths, among which 146 million are in children younger than 5 years of whom 101 million are in infants younger than 1 year. Measles vaccination is the single greatest contributor of lives saved by vaccination, preventing 93.7 million deaths out of total 154 million deaths prevented by vaccination globally. The vaccination has contributed for 40% of the decline in global infant mortality, 52% in the African region. In 2024, a child younger than 10 years is 40% more likely to survive to their next birthday relative to a hypothetical scenario of no vaccination. Increased survival probability is observed into adulthood as well, individuals aged 25 years are 35% more likely, and those aged 50 years are 16% more likely to survive to their next birthday

## Ongoing disease eradication and elimination initiatives

After eradication of smallpox in 1980, nine other eradication and elimination strategies have been established:
The Global Polio Eradication Initiative (1988)
Maternal and Neonatal Tetanus Elimination (1989)
The Measles & Rubella Initiative (2001)
The End TB strategy (2015)
The Global Health Sector Strategy on Viral Hepatitis (2016)
The Global Technical Strategy for Malaria (2016)
The Eliminate Yellow Fever Epidemics Strategy (2017)
The Global Strategy to Accelerate the Elimination of Cervical Cancer (2020)
The Global Roadmap to Defeat Meningitis (2020)