How India managed to win the battle against polio
Polio has been declared a "global emergency" by the Global Polio Eradication Initiative after "explosive" outbreaks in countries previously free of the disease.
It has launched a plan to boost vaccination in Nigeria, Pakistan and Afghanistan, the only countries where the disease is still endemic.
India, once regarded as one of the most challenging countries, was declared free of the disease in February.
Anuradha Gupta, from India's Ministry of Health and Family Welfare, said that despite the success, they remained very alert and vigilant.