A Valuable History Lesson

“Those who cannot remember the past are condemned to repeat it.”
–George Santayana (Spanish-born American Philosopher, Humanist and Poet, 1863-1952

I’m a bit of a history buff, and like most armchair historians who know something about medicine, it’s always interesting to try and work out why some civilizations underwent rapid collapse. Was the decline of Rome really due to malaria, lead pipes or societal malaise? Why did the huge Khmer Empire in Southeast Asia vanish in just a few years? Was it ecological failure, disease or pollution? The list goes on.

The map shows some of the major empires in Eurasia around A.D.1200. See how few still exist.

One of these historical puzzles seems to be close to solution, and provides important lessons for us today. In the second year of the Peloponnesian war, the city state of Athens was devastated by an epidemic known as the Plague of Athens. Historians and scientists have been debating the cause of the Plague for years. When I was a young schoolboy, the debate was already a century old.

According to historical records, the plague began in Ethiopia and passed through Egypt and Libya to Greece in 430-426 B.C.E. It forever changed the balance of power between Athens and Sparta, effectively ending the Golden Age of Athenian dominance in the ancient world. It is thought that up to one third of the Athenians, including their leader, Pericles, dies in the epidemic. Most of our knowledge about the Plague came from the fifth century B.C.E. Greek historian Thucydides, who himself was taken ill with the plague but recovered. Though Thucydides gave a detailed description, researchers have not managed to agree on the identity of the plague. Several diseases have been suggested, including bubonic plague, smallpox, anthrax and measles.

Now a study in the International Journal of Infectious Diseases helps answer this question that has puzzled historians for decades: What destroyed ancient Athens, the cradle of democracy? Analysis carried out by Manolis Papagrigorakis and colleagues from the University of Athens, using DNA collected from teeth obtained from an ancient Greek burial pit points to typhoid fever as the disease responsible for this devastating epidemic. Typhoid fever (or enteric fever) is an illness caused by the bacterium Salmonella Typhi. It is common throughout the world, more so in tropical and semitropical climates. It is transmitted by ingestion of food or water contaminated with feces from an infected person.

There are some classic physical symptoms of typhoid: In the first phase there is coughing, a fever, sweating and a rash of “rose spots,” particularly on the abdomen. Typhoid has a unique feature: normally when you get a fever your pulse rate increases. In typhoid the pulse slows. In the second phase of the illness people get severe headaches muscle pain and diarrhea. And it is the diarrhea that usually dehydrates and kills people. You may have heard about typhoid in the last few days after publication that a well-known terrorist was supposed to have died from it.

It is humbling to realize that entire civilizations have been put to the sword, not by force of arms, but by microbes. Climate change or a breakdown in sanitation of food inspection can all lead to a reappearance of typhoid: within the last hundred year there have been outbreaks all over the Western world, and it is endemic in many less developed countries.

I mention in Healing, Meaning and Purpose that one of the reasons for the persistence of the gene for cystic fibrosis is thought to be that carriers of the gene are resistant to typhoid.

We must never forget the power of micro-organisms and how rapidly they can re-appear if we let down our guard or if we neglect the impact of climate change on their growth and viability.

It is no coincidence that H.G. Wells vanquished the Martians not with guns, but with microbes.