The Bacteria That Helped To Defeat Napoleon

Different generations of leaders and soldiers learned the same lesson the hard way.  Both Napoleon and Hitler invaded Russia and both armies failed.  We now know from a study that two additional diseases plagued Napoleon’s troops along with hunger, cold, and harassment from Russian troops. 

In June of 1812, Napolean’s army of more than 600,000, Europe’s largest, crossed into Russia. Facing a much smaller Russian army, he believed he’d win in a month. But the Russians used the Fabian strategy, a scorched earth approach that involved retreating and avoiding large scale battles while destroying resources as they went. 

So even while Napoleon captured Moscow, it was abandoned and set ablaze with few supplies and winter coming on. By the time he retreated in October and crossed into France in December, just one-sixth of his army remained. Researchers studying DNA from the remains of those soldiers learned they had suffered from typhus and trench fever, but the methods they used could only identify microbes they specifically looked for.  

New recent work used more advanced techniques that could analyze millions of DNA fragments on soldiers’ teeth for a wide array of pathogens simultaneously.  This turned up two new bacteria responsible for decimating Napoleon’s army: one that causes paratyphoid fever and another that causes relapsing fever. Now we have a clearer picture of what happened in one of history’s major chapters.