Book Review

Rats, Lice and History

by Hans Zinsser

     Warfare has always been a part of human existence. So has disease. What if I were to tell you that the two are inextricably linked? That is the point that science historian Hans Zinsser attempts to prove in his semi-classic study Rats, Lice and History. While he makes a sweeping and somewhat superficial survey of Western civilization, he does have enough scientific credibility to prove his point.

This book does not get off to a great start. Although written in the 1930s, the author writes with a prose that resembles Victorian era essays using baroque sentences that meander on for a bit too long with elaborate detailing and excessive description. This isn’t necessarily a bad thing, I happen to like some 19^th century literature, but it feels a little out of place in the context of this mid-modern text. The first two chapters also left me wondering where the book would be going since they had almost nothing to do with rats, lice, or history. The second chapter, in particular, was a rant against modernist styles in literature where the author makes it clear that he has no appreciation for the likes of T.S. Eliot, Gertrude Stein, or James Joyce.

Moving on from there, Zinsser gives a lengthy overview of trade practices, disease, and warfare as they occurred in ancient times. We hear about the usual Greeks, Romans, and Christians up through the Middle Ages to the voyages of Columbus. By this point in my life I’m getting a little bored of every history scholar writing as if the world outside of Europe didn’t exist before World War II, but I just have to accept that that is how history used to be studied. In any case, the author points out that the use of ships for trade and war did a lot to spread disease since stowaway rats carried infected fleas that regarded the sailors as nothing more than food. Yes, like it or not, people are food.

One of the strongest points of the book’s first half is that diseases often weakened and killed more soldiers than combat actually did. He even goes so far as to make the point that disease could have been a more decisive factor in fighting than military strategy, skill, or execution. Now that is an idea that should deflate the myth of the courageous warrior. The science of the matter is that having large groups of people, be they confined on boats or engaging in military campaigns, in close proximity to each other make it easy for fleas and lice to spread sicknesses throughout the population at a rapid pace. Soldiers returning home or mingling with the people they conquer spread the diseases into the civilian population and then we have epidemics like the Black Death. You have to admit the idea is plausible and with Zinsser’s background in biology, he uses his knowledge of entomology to support the point.

After about one hundred pages of what eventually sounds like a bunch of babbling about wars, the narrative really takes off as Zinsser examines historical writings to locate the first mention of typhus. There isn’t much in the historical record that corresponds with the modern understanding of typhus symptoms and its origins are murky at best, but he develops a theory, one that he admits is not strong, that typhus originated in Asia and was spread by sea merchants to Western Europe via Cyprus during the Renaissance.

From there, Zinsser takes a big leap into the subject of human-animal relationships with chapters describing lice, mice, rats, and fleas which, along with humans, form a pentangonal track for typhus to travel along. His opinion of lice is surprisingly sympathetic while his take on rats is not so hot. Lice, he claims, are actually neutral vectors that catch typhus from humans. When they reproduce, they pass the typhus on to their offspring which spread among the human population and spread the disease further amongst humans. Typhus actually kills the host lice so spreading the disease does not benefit them in any way. They are innocent vermin that just happened to get caught in the crossfire of a war between humans and a disease. Rats, on the other hand, are nothing but pests according to the author. He thinks they serve no purpose in the world other than to cause problems. They are, in fact, part of the food chain and being the scavengers that they are, their ecological function in the world is to clean up the messes left by other creature like us. That is why they thrive in places that are full of human-made garbage. Useless? I hardly think so. But regardless of what you believe, the truth is that mice carry the fleas that transmit typhus to rats and those fleas transmit typhus to humans. The humans transmit it to lice and the lice transmit it to other humans. It’s a grim way of looking at people, but we do have to be reminded from time to time that we are not the magnificent species we claim to be. We might actually be little more than a dangerous parasite if looked at from Planet Earth’s point of view. In any case, this portion of the book is fascinating and brilliant; you can really see Zinsser at his best in these passages.

The rest of the book is all about typhus and he gets around to pointing out how bad of a problem it was during World War I. This brings up an interesting dilemma. If this book was inspired by the aftermath of World War I, is it fair to say that the event overly influenced the author in his analysis and conclusions? Or did the post-war realities shine a light onto a previously unexplored matter of human history, medical science, and entomology? I can’t say for myself because I know absolutely nothing about typhus or the science of epidemics. But I can say this book made me look at humanity in a new light which is saying a lot considering the thousands of books I have read in my lifetime.

Since the 1930s, scientists have learned a lot about typhus and other illnesses so it is fair to assume that some of the information in this book is dated. But Rats, Lice and History poses a significant question about human nature and our history. If wars are the primary way in which diseases spread and become epidemics or pandemics, wouldn’t it make sense to fight less of them or even eliminate them altogether? I have no idea how we could accomplish that, but if that question is the biggest takeaway you can get from this book, then the message transcends any dated scientific ideas it may contain. I’d say that the way Hans Zinsser presented just enough evidence to make that question stick in my mind is reason enough for it to be worth reading, even almost one hundred years after its initial publication.