The answer is China. Some say that it was traveled through the Silk Road while others believe that it arrived by ship. It was caused by a virus from fleas and carried by rodents. It arrived in Europe by traders from Genoa who came from Crimea. It was responsible for wiping out large populations in Europe, Asia and the Middle East. Symptoms of the plaque are swollen lymph glands, freckle-like spots, acute fever and vomiting blood. The victim would die in two to seven days.