NEW DELHI - Indian leaders are set later Tuesday to celebrate the eradication of polio, marking one of the country's biggest public health success stories which was once thought impossible to achieve.
President Pranab Mukherjee, Prime Minister Manmohan Singh as well as the health minister and the head of the World Health Organisation are all due at a New Delhi stadium to celebrate "India's victory over polio", the information ministry says.
India, long one of the biggest sources of the paralysing virus, has gone three years without a new case, which means it will soon be certified as having wiped out the scourge.
On the three-year anniversary of the last case, on January 13, Health Minister Ghulam Nabi Azad hailed the "monumental milestone" and promised a celebration in honour of the officials, volunteers, NGOs and UN agencies which made it possible.
Polio is a virus spread through faecal matter that affects the central nervous system and can leave its victims with withered limbs or paralysis.
There is no cure but it can be prevented through mass vaccination programmes.
India's poor sanitation, mass internal migration and dilapidated public health system made experts once fear it would be the last country to eradicate the disease.
There are now only three countries where polio is endemic - Pakistan, Afghanistan and Nigeria - and health workers say progress is being made towards global eradication.
Isolated polio outbreaks in the Horn of Africa and war-racked Syria emerged as new causes for concern in 2013, however, and polio vaccination workers in Pakistan are still being killed by the Taliban.
The wretched sight of crippled street hawkers or beggars on wheeled trolleys will also endure in India as a legacy of the country's time as an epicentre of new cases.
In the absence of official data, most experts agree there are several million survivors left with withered legs or twisted spines who face discrimination and often live on the margins of society.
India reported 150,000 cases of paralytic polio in 1985 and still accounted for half of all cases globally in 2009, with 741 infections that led to paralysis.
In 2010 the number of victims fell to double figures before the last case on January 13, 2011, when an 18-month-old girl in a Kolkata slum was found to have contracted it.
The girl, Rukshar Khatoon, is now attending school and leads a "normal life", although she still suffers pain in her right leg, doctors and her parents have told AFP.
Tuesday's celebration in New Delhi will be held in the Talkatora indoor stadium at 05:00 pm (1130 GMT).
Official certification by the World Health Organisation that India has eradicated polio is likely to come next month.