The cost of eradicating polio may seem high, but with a last concerted effort we will pass on a world free of the disease for ever, writes David L. Heymann.
David L. Heymann, M.D. is head and senior fellow of Chatham House Centre on Global Health Security (London).
When I was a young doctor having just completed my medical training, I had the once-in-a-lifetime opportunity to participate in one of humanity’s most ambitious efforts: to eradicate smallpox. While smallpox may seem like a distant memory for children born today, there was a time not too long ago when the disease, like polio, was a very real threat and in the 18th century it killed an estimated 400,000 Europeans every year.
Using a vaccine pioneered by British scientist Edward Jenner in the late 18th century, health workers around the world searched for people displaying the distinctive rash of smallpox, isolated them and provided whatever medical care they could. Then, they vaccinated everyone who had been in contact with the person, effectively forming a ring of protection around the infected individual.
In 1967, the year when intensive eradication activities began, smallpox killed over 2 million people a year, mostly in developing countries. On 8 May, 1980 – only thirteen years later – the disease was declared eradicated at the 33rd World Health Assembly in Geneva, Switzerland, thanks to committed partners and strategies like the ring of protection.
After smallpox eradication, our only question was: what disease would be next? In 1988, the world embarked on its journey to eradicate polio – a dreaded disease known for its ruthless, lifelong paralysis, and for which there is no cure.
Polio, like smallpox, does not hide in animals – it only infects humans. And we have very effective vaccines to prevent it. This makes polio the perfect candidate for eradication. All we have to do is provide the vaccine to everyone, everywhere.
Of course, this is easier said than done. By the early 2000s, the world had managed to eliminate polio in all but six countries – Europe was declared polio free in 2002. Around that time, I joined the eradication effort. My job was to help end polio in endemic countries and ensure it didn’t resurface in countries where it had been eliminated.
I quickly learned that polio eradication was much more complicated than smallpox eradication had been. While every person infected with smallpox could be easily identified by a characteristic rash, polio is often invisible until it’s too late. For each child paralysed there are up to 500 infected who show no symptoms, but can still spread the virus to others. And so the only way to stop polio for good is to vaccinate every single child, so that she can neither be paralysed by the disease herself nor spread it to others.
When the polio eradication effort was launched, polio had already disappeared from most industrialised countries, but continued to paralyse 1,000 children per day around the world, mainly in less developed regions. Last year, there were only 37 children paralysed by polio in the entire world. But 37 children paralysed by polio is still 37 too many. And polio in any country is a threat to all countries, as history has shown us time and time again.
Today, the eradication programme has succeeded in eliminating polio in all but three countries: Nigeria, Pakistan and Afghanistan. Even so, one exported case from any of these countries to a neighbouring region is all it takes to backpedal and put the whole world at risk. Fortunately, the polio eradication effort has remained well prepared over the years. Last summer, the programme rapidly responded to an outbreak in Nigeria by organising emergency immunisation campaigns throughout the surrounding regions, which are still underway today. It’s likely thanks to these efforts that polio hasn’t reappeared in regions where it had been eliminated.
But containment and emergency response alone will not get us to where we need to be. We cannot afford to lose sight of our ultimate goal: eradication.
While some believe the economic cost of eradication is too high, the cost of not staying the course is even higher. It’s only by getting to zero cases anywhere in the world that children everywhere will be protected. And now that we are a stone’s throw away from ending polio for good, it’s more important than ever for the international commitment to science, foreign aid and polio eradication. Ending polio is a gift not only for this generation, but also for every generation in humanity’s future.
In the 20th century, smallpox claimed more than 300 million lives. In the 21st century, it will not claim any. Polio will have a similar legacy. Just as my children do not know a world with smallpox, their children will grow up in a world free of polio. Europe has led the world in scientific innovation, overseas aid and polio eradication and at the Atlanta Rotary Convention on 12 June, 40,000 Rotarians and global health leaders will unite to ensure the polio effort is effectively funded so it can reach every last child with the polio vaccine.
In this new era of sustainable development, it’s critical that the European Union continues to play a leadership role in one of the most sustainable global public goods imaginable: the eradication of the second human disease in history.