For many of us, the threat of contracting polio belongs in the past. We think of black and white photographs showing patients in wheelchairs or lying in an 'iron lung' to help them breathe. But for people in polio's last strongholds, the disease remains as real a threat today as it was 50 years ago.
Polio is a swift and vicious disease caused by a virus, affecting mainly children under five. It is spread through person-to-person contact and can enter the body through water tainted with sewage or contaminated food. Within hours, polio can leave its victim permanently paralysed.
But there is hope. Biologically, polio could be eradicated, and over the last half-century, eradication efforts have gathered pace.
Following the introduction of the first vaccine against polio in 1955, a mass vaccination programme marked the beginning of the end for polio in the developed world.
Since 1988, the number of polio cases has dropped by over 99%. The World Health Organization (WHO) and its partners have now set their sights on eradicating polio by 2018.
But as World Polio Day dawns, the battle to make this disease history continues.
Polio remains endemic in three countries - Afghanistan, Nigeria and Pakistan - and recently, we have seen a worrying spate of cases in Somalia. WHO warns that a failure to eradicate polio from its final strongholds could result in as many as 200,000 new cases every year, within 10 years, all over the world.
While people are still at risk of contracting this disease, our efforts to eradicate polio - and to keep it at bay after eradication - must be sustained. As well as making sure that vaccines reach those who need them, we must continue to develop new tools in our arsenal against polio.
As a global healthcare company, our commitment to supporting the eradication effort is manifold. Our role includes manufacturing vaccines and using our research expertise to explore fresh ways of tackling polio. Meanwhile, our innovative business model means we can price vaccines to reach those who need them while also investing in next-generation products.
Our history of supporting the polio eradication effort dates back to the 1950s, when we were among the first companies to begin manufacturing a vaccine. We have supplied the oral polio vaccine (OPV) ever since. OPV programmes are relatively inexpensive and, because it is taken orally, the vaccine can be distributed by volunteers without the need for a trained healthcare worker or sterile injection equipment.
In 2012 alone, we provided over 400 million doses to the Global Polio Eradication Initiative (GPEI), a public-private partnership led by national governments and WHO. We have committed to meeting at least 30% of the GPEI's polio vaccine requirements, procured through UNICEF, up to 2017. This equates to around 1.5 billion doses.
The campaign by the international community to eradicate polio has been diligent and profound, supported by organisations such as UNICEF and the Bill & Melinda Gates Foundation. Thanks to these collaborative efforts, we are arguably closer to eradication than we ever have been. At GSK, we remain committed to playing our role in supporting WHO's 2018 eradication objective by providing vaccines to UNICEF until every country in the world is declared 'polio free'.
Across the public health community, we must keep collaborating and keep innovating if we are to better understand polio and find new measures to tackle it. And, if we do manage to eradicate polio, we will need to ensure that it does not resurface.
In countries where polio has been eradicated, OPV - which is a live attenuated vaccine - will be phased out and replaced with the inactivated polio vaccine (IPV) to prevent the extremely low but possible risk of polio re-emerging from the vaccine itself.
Already, we produce and supply IPV to a variety of countries, primarily developed markets, which are implementing immunisation programmes. This enables us to invest to develop lower cost combination vaccines for the developing world that contain IPV alongside vaccines for other diseases such as diphtheria or tetanus.
The battle to eradicate polio is not won yet. Recent outbreaks remind us that it is a tenacious opponent. Putting a stop to the final 1% of polio cases could be the toughest challenge. That the world has so far only eradicated one infectious disease - smallpox - reminds us of the scale of our task. But by marshalling our resources and staying vigilant, we could banish polio for good.