News and Insights

Celebrating 50 years of the Expanded Programme on Immunization

June 6, 2024

Whether you’re an ardent supporter or a staunch critic of vaccines, join us as we delve into the remarkable achievements, persistent challenges, and promising future prospects of immunisation programmes worldwide. Discover how these tiny miracles have transformed public health, the obstacles they face, and the innovative strides that lie ahead in the ongoing battle against vaccine-preventable diseases.

On May 23, 1974, the 27th World Health Assembly witnessed the adoption of a seemingly unassuming resolution. This single-page document laid the foundation for one of the most transformative initiatives in global public health: the Expanded Programme on Immunization (EPI). This programme later renamed the Essential Programme on Immunization, has been a cornerstone in the fight against communicable diseases, dramatically improving childhood survival rates and eradicating deadly illnesses. As we commemorate 50 years of the EPI, it is essential to reflect on its monumental achievements, the hurdles it faces, and the promising future ahead.

The Genesis of the EPI

The inception of the EPI was driven by the recognition of the “immense contribution” of immunisation in controlling major communicable diseases. The resolution urged WHO Member States to develop vaccination and surveillance programmes against diphtheria, pertussis, tetanus, measles, poliomyelitis, tuberculosis, and smallpox, which were the leading causes of child mortality. WHO’s then Director-General, Halfdan Mahler, was tasked with intensifying activities to assist countries in this critical endeavour. This pivotal moment marked the beginning of a global effort to ensure that children everywhere had access to life-saving vaccines.

A Legacy of Achievement

Over the past five decades, the EPI has been instrumental in several historic public health victories. One of its most notable achievements was eradicating smallpox in 1980, a feat accomplished amidst the geopolitical tensions of the Cold War. The programme is now on the verge of eradicating polio, with only a few cases reported in Afghanistan and Pakistan. According to Kate O’Brien, WHO’s Director of the Department of Immunization, Vaccines, and Biologicals, the EPI has made a “massive contribution” to child survival, with an estimated 101 million infant lives saved over the past fifty years.

– Vaccination doesn’t just save lives; it also prevents the long-term consequences associated with severe disease, especially polio.
– On average, for every life saved, 66 years of full health were regained, translating to 10.2 billion years of health gained. This takes into account years of disability caused by disease.

When the EPI was launched, only 5% of the world’s children were vaccinated against major diseases, primarily in high-income countries. Thanks to the EPI’s efforts, every country has a national immunisation programme. The EPI recommends 13 vaccines for all countries, including those against rubella, hepatitis B, and human papillomavirus (HPV), to prevent cervical cancer. The programme also supports 17 region or context-specific vaccines, such as yellow fever, cholera, and malaria.

Overcoming Challenges

Despite these remarkable achievements, the EPI faces numerous challenges as it looks to the future. The COVID-19 pandemic severely disrupted national immunisation programmes, leading to 67 million children worldwide missing one or more vaccines. This disruption has caused significant outbreaks of vaccine-preventable diseases, with 50 countries reporting large measles outbreaks in 2023 alone, double the number from 2022. O’Brien emphasises the urgency of addressing these setbacks: “Every government that has had backsliding needs a plan, and most governments have made a plan and are starting to deploy. We have a very narrow window to get this completed.”

One critical challenge is reaching older children who missed routine immunisation. Ephrem Tekle Lemango, UNICEF’s Chief of Immunization, notes that many unimmunised children are now older than two years, requiring new approaches to reach them and prevent the continuity of vaccine-preventable disease outbreaks.

Sustainable funding for national immunisation programmes remains another significant hurdle. Countries facing debt crises, conflicts, and climate change need consistent financial support to maintain their immunisation efforts. Aurélia Nguyen, Chief Programme Officer at Gavi, highlights the economic impact of vaccination, stating that Gavi programmes have generated $220 billion in financial benefits in supported countries since 2000.

Innovations and Future Prospects

Looking ahead, the EPI can leverage several promising innovations and strategies to overcome its challenges. Scientific advancements are paving the way for new vaccine delivery methods, such as microarray patches that can be easily administered at home and potentially delivered by drones. This technology could revolutionise access to vaccines, especially in hard-to-reach areas.

Community health workers are another untapped resource with the potential to improve vaccine coverage significantly. With approximately 1 million community health workers across Africa, empowering them to administer vaccines could help reach the last mile in immunisation efforts. Lemango stresses their importance: “They are the most trusted source of information for communities. If we can skill these community health workers to vaccinate and provide the required vaccines, the likelihood of reaching the last child could be much more imminent.”

Moreover, the introduction of new malaria vaccines represents a major milestone. Eight African countries have already rolled out a malaria vaccine, with more expected to follow in 2024. These vaccines promise to reduce the burden of malaria, which remains a significant public health challenge in many regions.

The Role of Global Partnerships

The EPI’s success has been bolstered by strong global partnerships. The Global Alliance for Vaccines and Immunization (Gavi) launch in 2,000 marked a turning point in efforts to close the equity gap in vaccine access. By pooling funding and demand, Gavi has enabled low-income countries to afford and deploy vaccines that were previously accessible only to high-income nations. This collaboration has been crucial in raising immunisation coverage and introducing new vaccines into the EPI.

In emergencies, organisations like Médecins Sans Frontières (MSF) play a vital role in vaccinating children who have missed routine immunisation. However, improving coordination and speeding up responses during outbreaks remain critical challenges. Kartini Gadroen, MSF’s Vaccination Advisor, highlights the need for quicker vaccine access in humanitarian crises, pointing to a measles outbreak in Goma, DR Congo, in March 2024, which could have been prevented with faster intervention.

Political Will and Financial Commitment

For the EPI to continue its success, strong political will and financial commitment from country governments are essential. O’Brien underscores the importance of political leadership, stating, “What has been achieved can all be lost…unless the political will, leadership, and the political engagement is there. So what we’re really calling on at this 50th anniversary is for all political leaders to be inspired by what has been gained. It’s on them to assure their legacy is not that we go backwards.”

Lemango echoes the call for political commitment, pointing out that reaching the last child remains challenging for global development efforts, particularly in areas affected by conflicts and humanitarian crises. Ensuring sustainable funding and maintaining political support are crucial to overcoming these barriers and continuing the progress made over the past fifty years.

Zero Dose Children

Zero-dose children, those who have not received any routine vaccinations, are often found in the most marginalised and vulnerable populations. This issue arises due to many factors, including geographical, socio-economic, and political barriers. Many of these children live in remote or conflict-affected areas where healthcare infrastructure is either non-existent or severely disrupted. Additionally, socio-economic disparities mean that families in impoverished regions lack access to healthcare services and information. 

Cultural beliefs and misinformation about vaccines can also significantly lead to vaccine hesitancy or outright refusal. Furthermore, political instability and governance challenges hinder establishing and maintaining effective immunisation programmes. Addressing the plight of zero-dose children requires a concerted effort to overcome these barriers through targeted outreach, education, and strengthening health systems to ensure equitable access to life-saving vaccines.


As we celebrate the 50th anniversary of the Expanded Programme on Immunization, it is clear that the initiative has been a cornerstone of global health, saving millions of lives and bringing hope to countless families. While challenges remain, the EPI’s legacy of success provides a strong foundation for future efforts. By embracing scientific innovations, leveraging community resources, and fostering global partnerships, the EPI can continue to protect the world’s most vulnerable populations and build a healthier, more equitable future for all. The next fifty years hold immense promise, and with sustained commitment and collaboration, the EPI can achieve even greater heights in the fight against vaccine-preventable diseases.

TAGS: Global Health Impact, Health

POSTED BY: Christopher Nial

Christopher Nial