The original version of this article appeared on Ensia. Near the corner of Broadwick and Lexington in London’s Soho neighborhood, a single spot on the ground has influenced more than 150 years of urban development. It’s the location of a water pump that in 1854 physician John Snow pinpointed as the source of contamination leading … Continue reading As Cities Grow More Crammed and Connected, How Will We Discourage the Spread of Disease?