In pursuit of a polio-free world, more than 2.5 billion children have been immunized against the crippling disease and around 16 million cases of paralysis have been prevented. There were over 350,000 cases of polio in 1988, compared to only 37 last year — the progress that has been made as a result of the world’s polio eradication efforts is remarkable.

And this progress extends far beyond interrupting polio transmission.

Polio immunization programs in low-income and developing nations are working to advance health systems and prevent emergencies within vulnerable communities, becoming crucial driving forces in the push towards universal health care.

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Since its formation almost 30 years ago, the Global Polio Eradication Initiative (GPEI) has put millions of skilled health workers on the ground in regions with formerly limited access to health services, reaching an unprecedented number of children.

These workers don’t just deliver polio vaccines. They spend over half of their time working to protect children from other dangerous diseases like measles and rotavirus by introducing and bolstering routine immunization programs, according to the GPEI. In fact, GPEI’s network of polio staff constitutes the single largest source of support for immunization services in low-income countries.

In India alone, National Immunization Days see 2.5 million vaccinators and 155,000 supervisors working together to deliver a range of lifesaving vaccines to millions of children. The polio program in the northern Indian state of Bihar contributed to the increase of routine immunization coverage from 19% to 67% between 2005 and 2010, simultaneously achieving polio eradication.

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Workers are also dedicated to delivering other health services relating to the issues of nutrition, sanitation, and disease prevention to children that were previously unreachable.

Nomadic children in Nigeria, migrant children of brick kiln workers in India, and children in the midst of conflict in Sudan and Somalia are all reached by the polio program.

One of the most striking ways in which polio elimination and surveillance programs have become critical to supporting the overall health and wellbeing of communities is by increasing their capacity to prevent and respond to looming health threats and emergencies.

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From stopping deadly outbreaks to minimizing the health consequences of natural disasters, the impact of the worldwide quest to eradicate polio has been astonishingly wide-reaching.

Here are three times that the fight to end polio stopped another potential health emergency in its tracks.

1. Cholera in Nepal

Nepal has been polio-free since 2010, but maintaining high levels of immunization coverage and remaining vigilant to signs of infection are crucial to preventing its re-emergence. GPEI-funded community health workers are essential to carrying out this plan, which is why, just two years ago, when the country was hit by a devastating earthquake that killed 9,000 people and injured almost 22,000, there were trained personnel onsite that were able to assess and respond immediately to the health threats that arose in the aftermath.

The damage caused by the earthquake meant that people were living without shelter, proper sanitation, or clean drinking water, and the risk of a cholera outbreak was severe. By deploying the polio eradication teams in the wake of the disaster, a major outbreak of cholera was averted and the already dire situation in Nepal was not made even worse.

2. Zika in the Americas

There is growing evidence that Guillain-Barré syndrome is caused by Zika virus infection, and as such, it has become an important clinical marker for detecting the transmission of Zika. It is therefore imperative that at-risk regions implement rigorous Guillain-Barré syndrome surveillance measures.

To that end, the World Health Organization emphasized the value of polio assets in curtailing the extent of the health emergency in the Americas in a paper demonstrating the importance of utilizing existing polio surveillance systems to monitor and minimize the transmission of Zika.

3. Ebola in Nigeria

When Ebola began to spread rapidly throughout West Africa in 2014, the established polio eradication and surveillance infrastructure was used to detect and stop Ebola transmission in Nigeria before the deadly virus was able to really take hold.

The Ebola outbreak lasted for 21 months in the rest of West Africa and resulted in 11,315 deaths. In Nigeria, the outbreak was contained as polio health workers were able to reach 27,000 households and carry out 19,000 contact tracing visits.

This meant that the Nigerian outbreak lasted only three months and resulted in only seven deaths.

Polio infrastructure was used to facilitate Ebola surveillance in the worst affected countries, thereby helping to prevent what was already a human catastrophe from being further exacerbated in Liberia, Guinea, and Sierra Leone.

Other humanitarian crises for which the polio program has provided invaluable assistance include the SARS epidemic of 2002, the Asian tsunami of 2004 and the floods in Pakistan in 2010. In this way, the battle to end polio has become part of a much larger war, in which the right of all people to good health and wellbeing is at stake.

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In fact, world leaders documented the “significant contribution that the polio related assets, resources and infrastructure... have on strengthening health systems and advancing universal health coverage” in the G7 Ise-Shima Vision for Global Health, using this as a basis to reaffirm their commitment to working towards achieving global polio eradication targets.

That is why continuing on the path towards polio eradication is so important. Together, the world can work to end this devastating disease, building strong health systems and advance the movement for universal access to healthcare along the way.

Call upon world leaders to prioritize the fight to end polio here.