It is the kind of line to prick a newspaper editor's conscience. Early in his new book, The End of Poverty, Professor Jeffrey Sachs comments that every day our newspapers could report "more than 20,000 people perished yesterday of extreme poverty". But it doesn't work that way. The story is too big for the news.

The death of more than 20,000 people on a single day would be one of the most momentous stories of the year - full of heartbreak and horror, particularly as so many of the victims were children.

The headlines would be massive, the news coverage extensive, the analysis compelling and in the days ahead, the letters page would be full of reader feedback.

But because this event happens every day of the year, for complex reasons that are hard to solve, it makes little news.

The problem with worldwide poverty and the unimaginable death toll, is that it is happening everywhere, all the time.

There is no sudden trigger or cause. It is a disaster without a single cataclysmic event. No single site of the tragedy. A mundane horror.