The Ghost Map, by Steven Johnson

Perhaps a book about cholera outbreaks isn't the best idea for a self-proclaimed germophobe...but then again, it's a really interesting book! "The Ghost Map" is about an outbreak of cholera in a London neighborhood in 1854, a tragic event that led to a doctor named John Snow (no relation to the Starks [apologies for that ridiculous GoT joke]) figuring out that cholera was waterborne and not, as contemporary theory dictated, caused by "bad air." It was a momentous work of investigative science, the echoes of which are still quite strongly felt today in such areas as public health, urban planning, scientific method, epidemiology, and even social mapping programs such as Yelp. Johnson is an engaging writer, skillfully explaining the more complex scientific concepts as well as telling the story of the outbreak like a modern day murder mystery. He goes a bit off the rails toward the end, descending into fearmongering about the chances of a nuclear detonation in a major urban center; luckily, this unnecessary and marginally related section is rather small, and only detracts a little bit from the work's overall strength. I just wish I hadn't read it while eating...