Saturday, August 11, 2007

The Ghost Map, by Steven Johnson

After reading The Great Influenza I became newly interested in the way diseases are spread. That book details not only the lives of the many persons involved in research and public health responses to the influenza of 1918, but also details the lives of the virus itself. I was interested in another outbreak, this time of cholera, in London in 1854. Specifically, I was interested in The Ghost Map.

The cholera outbreak lasted just about a week, the worst of it anyway, but it was horrifying in its proportions. It also was hardly the first or last time the disease devastated a city. This time, according to Steven Johnson's uncomplicated telling, science ultimately got the better of it.

The two principals responsible for discovering and alerting the health boards and the population to how the disease is transmitted were John Snow, physician, and Henry Whitehead, cleric. Both were young at the time and both observant and given to a questioning state of mind. They ultimately clashed with the popular theory at the time that diseases such as cholera are spread by "miasma" - smells in the air. The worse the smell, the more saturated is the air with disease. Snow suspected, instead, that water carried the disease, even though at the time there was no germ theory and he had no idea what form it took. Whitehead used his social skills and observant mind to bring together the closest to absolute proof that Snow was right.

The story doesn't end with this discovery. All do not live happily ever after.

The public health response was less than ideal, and it was several years before Snow's theory was accepted and acted upon. The response was remarkable, though. A major sanitary sewer project was undertaken that is still in use today. When it was complete the citizens were no longer drinking each other's bodily waste. And cholera could no longer get a foothold.

The real thesis of The Ghost Map is not the telling of this story. It is the implications for urban life today and in the future. Before Snow burst on the scene cities were reaching such proportions that residents lived in daily fear for their lives. It was commonly assumed that large cities would reach some critical mass when the numbers could no longer sustain themselves, spelling the death of the metropolis. Dealing with the daily waste of large numbers of persons appeared an impossible task that would ultimately limit the viability of the city itself. Snow's discovery and the construction of a workable sewer system changed all that. Which is why Johnson's position is that science can conquer almost everything.

It is only in the epilogue that Johnson's short, readable book that this thesis comes to life, rather like an indomitable puppy dog, expecting only the best. He expounds briefly on how viruses and bacteria mutate rapidly (within a day a virus can go through thousands of variations) and then blithely states that our masses of scientists, with our modern technology, can surely keep ahead of this curve.

Even if it were true that scientists are even now creating every possible variation on a virus and finding a vaccine for each, he ignores another significant element: the public health response. We have seen in this book that public health officials held the old-line views on miasma and hindered rather than helped the response in 1854. Similarly during the Katrina hurricane response we found that although the science was there it was not in use.

I can't buy Johnson's cheery prognosis. He ignores the far more complicated science of these disease elements that is described in great detail in that other book, The Great Influenza. He largely ignores the ignorance of the public at large and its alarming attachment to the supernatural. Most importantly, he ignores the political animal.

This book is an engaging story of one outbreak. It is well-written and informative and it includes genuine heroes. Read it for that story. For any theory of the future it would be better to read a more thorough discourse on public health issues, including The Great Influenza.

book rating: 3.5 out of 5 stars

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