By today’s standards, enteric fever, which includes typhoid and paratyphoid, is easily treatable and preventable – but in the days before antibiotics and vaccines, outbreaks of these diseases were so devastating that they could endanger entire civilizations. Researchers have known since 2006 that typhoid fever may have been responsible for the great “plague of Athens” in the 5th century B.C., which killed 100,000 people – a third of the city’s population – and led to the eventual dissolution of their empire. But enteric fevers’ ruinous impact did not stop there. As it turns out, enteric fevers may be responsible for the downfall of not one but two great civilizations.