John Snow Knows How to Save the World

London, 1849, you are a doctor and the dreaded disease, Cholera, is literally hitting the city the like the Bubonic plague. Your neighbor was fighting fit on Monday, and Wednesday morning you watched him go out on the corpse cart. The epidemic will go on to take over 50,000 lives before petering out a few months later. But based on its track record, you know it will be back.

What do you do? If you’re John Snow, anesthesiologist and part-time medical investigator, you march through the most desiccated areas of your stricken city to get to the bottom of what’s causing this horrible plague. And through your sleuthing and surprising friendship with a neighborhood priest, you actually discover not just the root of the plague, but the answer to keeping it from coming back ever again.

This is the story in “The Ghost Map” by Steven Johnson.

Without dialog, world building, or fictional device, Johnson takes us on a fun, interesting, and informative ride with Victorian anesthesiologist, John Snow and Broad Street priest, Henry Whitehead as the two men live and deal with the Cholera epidemics that ravaged a very stinky, fecal-filled London from 1830 to well into the 1880s.

Cholera, the fatal and waterborne intestinal microbe that would claim literally millions of lives over a stretch of about fifty years was thought to be an incurable menace that only hit the most destitute and morally debauched members of society due to the “miasma” or “bad smelling air” theory that permeated the medical doctrine of the 19^th Century.

John Snow felt differently since he happened to live near the line separating the “Debauched” from the “Moral” and he, along with priest Henry Whitehead, noticed that Cholera didn’t ask to see your community service record or church attendance before taking up residence in your intestine.  What they did find was that citizens taking water from certain street pumps were the ones winning the one-way ticket to Deathville.

Johnson’s writing and research weave a very real picture of what Snow and Whitehead faced trying to change the minds of the medical big-wigs, as well as the global and historical impact of how their findings reshaped city living in today’s world.

Aside from the Epilogue which feels like Johnson shoved in all the rest of the research he couldn’t really fit in to the actual book, but didn’t want to leave out, “The Ghost Map” is an excellent and compelling read about the power of one man’s dedication to public health, and the importance of good sewer systems.