Antonine Plague

The Antonine Plague of AD 165 to 180, named for the emperors Marcus Aurelius and Lucius Verus of the Antonine dynasty and also known as the Plague of Galen after the Greek physician who described it, was a prolonged and destructive epidemic that affected the Roman Empire. It was possibly contracted and spread by soldiers returning from a campaign in the Near East. Scholars generally believe the disease was smallpox, based on skin eruptions described as red and black covering the whole body, although genetic evidence suggests severe smallpox emerged in Europe later; measles has also been proposed as a possible cause. Ancient sources broadly agree the disease likely first appeared during the Roman siege of Seleucia in the winter of 165 to 166, during the Parthian campaign, then spread westward, reaching Rome by 166. Death toll estimates range from five to ten million people, roughly ten percent of the empire's population, with an estimated twenty five percent fatality rate among those infected.