Sometime about 1338 AD, an earthquake or some other natural calamity began what would become the most terrible outbreak of any disease known to man. After outbreaks in Asia, which stretched from China to India, Persia, Syria, and Egypt and Asia Minor, this disease traveled along the Silk Road to the town of Kaffa. The disease rode inside small insects, which could live between six months and a year without the benefit of a human or animal host. The insects in turn probably traveled along the Silk Road hidden safely inside marmot furs, which were a popular and ready source of fur of the time. It took many years for the disease to make the long trip over the Silk Road to Kaffa. Traders would bypass towns that had outbreaks of the disease. But by 1346, the plague, Yersinia pestis, had reached the Black Sea port of Kaffa, and was ready to make its final jump via the trade ships to Europe.
             In the year 1346, war broke out in Kaffa between the Christian Italian merchants and the Muslim citizens in the area. The Muslims asked their Khan for help in expelling the Christians from the city. Yersinia pestis found the ideal situation to spread itself among the population. Rats lived among humans in close proximity. The thatch roofs of the dwellings and poor sanitation of the time caused a dramatic increase of the rat population. Ceratophyllus fasciatus, the fleas that carry Yersinia pestis, migrated easily from rat to stock to human, so that by the end of a year of siege, the plague erupted among the forces of the Muslim army. The Mongol Prince, Janiberg, recognized that the disease that afflicted his forces was extremely infectious, and ordered the dead from his army be catapulted over the walls of the city and into the opposing army. This early example of germ warfare was well documented by Gabriele de' Mussis, who wrote:
             "What seemed like mountains of dead were thrown into the city, and the Christians could not hide...