The past two decades has seen a huge improvement in global access to safer drinking water and decent sanitation, the UN said Thursday.
But the world's poorest communities continuously remain sidelined, Agence France-Presse reported.
Providing better drinking water and sanitation is the bedrock of the battle against diseases such as cholera, diarrhea, dysentery, hepatitis A, and typhoid.
"It's really an issue of addressing excreta, faeces, poo, I can even say shit. This is the root cause of so many diseases," said Bruce Gordon, coordinator of the water and sanitation arm of the World Health Organization.
Diarrhea related to poor water, sanitation and hygiene kills 842,000 people every year, Gordon said.
At the end of 2012, 89 percent of the globe's population had access to improved water supplies, up 13 percent from two decades ago, the WHO and UNICEF said in a report.
In UN jargon, an "improved drinking water source" protects the supply from contamination, notably by faeces.
"But despite the progress, 748 million people-roughly half of them in Sub-Saharan Africa and most of the rest in Asia-still used unimproved water sources," AFP reported. "The bulk of them lived in rural areas."
Access to "improved sanitation facilities", which separate excreta from human contact, was also examined by the study.
By the end of 2012, 64 percent of the global population used such facilities, a rise of 15 percentage points since 1990, the report found.
"Compounding the lack of access to decent sanitation, a billion people worldwide still defecate in the open air, including 600 million in India, the study found," AFP reported. "Open air defecation-which the report noted is a matter not only of poor sanitation but also of cultural acceptability-can all too easily undermine efforts to improve water supplies."
"It's a matter of demand by the community. They all demand water, but not all of them demand sanitation. What is shocking is the picture of someone practicing open defecation and on the other hand, having a mobile phone," said Maria Neira, the WHO's public health chief.
