What does 2.5 billion mean? If you think dollars in your pocket, 2.5 billion pretty much means you are set for life. In 2007, 2.5 billion described the number of iTunes music sales as well as the number of mobile phones in use. But 2.5 billion also describes the number of people who wake up each day with nowhere to go to defecate. So what do those people do? Defecate in the street. And that spreads disease.
"It is scandalous that in 2009 [the diarrhea death toll] is like four jumbo jets of children crashing every day. Human waste is a fabulous weapon of mass destruction."
Rose George, author of The Big Necessity: The Unmentionable World of Human Waste and Why it Matters