In a bid to solve some of India's worst health problems, one village in the country's north is fining people caught defecating outside.

Key points: An estimated 100,000 babies die in India annually due to poor sanitation

An estimated 100,000 babies die in India annually due to poor sanitation 650 million Indians either don't have or don't use a toilet

650 million Indians either don't have or don't use a toilet Prime Minister Narendra Modi has promised toilets for all Indians

Poor sanitation is blamed for persistent malnutrition and child stunting, and changing centuries-old habits is not proving easy.

A group of women applauded as tiny fines were imposed on villagers caught going to the toilet outside.

"We told you — if anybody defecates in the open, we'd fine them, said Shakuntala Devi, a respected elder among the women of Mewat in Haryana, not far from New Delhi.

"Ten rupees is a lot for us poor people, that is what we charged them, and now nobody goes," she said.

A group of women attend a toilet meeting in Mewat, Haryana. ( ABC News: James Bennett )

Across India though, its a different story. People squatting in fields, on the railway tracks — anywhere there is space, with or without privacy — is a common sight.

Around 650 million Indians either don't have or don't use a toilet.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 3 minutes 5 seconds 3 m 5 s A matter of survival: Indian village fines citizens who don't use toilets ( James Bennett ) Download 5.7 MB

"We lose 100,000 babies a year due to poor sanitation," said Madu Krishna, the Gates Foundation program director for water sanitation in India.

"Poor sanitation leads to diarrhoea and infectious diseases, especially of the gastrointestinal tract."

Pregnant women and babies are at particular risk, and getting sick has lifelong effects as malnourished babies' brains and bodies simply don't develop properly.

"Lack of nutrition leads to cognitive impact, it leads it leads to overall poor physical development but also mental development," Ms Krishna said.

Ambitious goal to end open defecation by 2019

Stunting, one of India's most intractable problems, affects nearly 40 per cent of Indian children and has been labelled "India's shame" by former prime minister Manmohan Singh.

Current Prime Minister Narendra Modi has vowed to provide toilets for all in just three years' time, as part of his Swachh Bharat [Clean India] policy, an initiative which draws on Mahatma Gandhi's legacy urging Indians to take pride in cleanliness.

But the promise to end open defecation by 2019 is an ambitious, and some believe, unrealistic goal.

Ms Krishna says building toilets is one thing, but changing people's minds is critical.

"Slowly we're moving the needle to behaviour change, which is a very big part of making people use safe sanitation," she said.

In Mewat, alongside the fines, that means educating people on the link between toilets and health.

Among the villagers, 55-year-old Mehram Habeeb admitted she never used a toilet until one of her sons got sick, which spurred her to save up.

"It was very difficult, my son fell ill and needed treatment," she said.

"[After that] we didn't care if we ate or not, or what our circumstances were, we just wanted to get a toilet."

She said having a toilet has given her privacy and dignity, and now enthusiastically spreads the word among fellow villagers.

But even between word of mouth and Government support, it is widely thought spreading that message across India will take 10 years at least.