<human>:  When did the Black Death in Indonesia start and how many people died?
<bot>: The Black Death started in 1347 and lasted until 1351. It killed about a third of the population of Europe. It was caused by a bacterium called Yersinia pestis, which is spread by fleas. The plague was so deadly because it was so contagious. It was spread by fleas that lived on rats, which lived in the walls of houses. The fleas would bite people and then the people would bite other people, and then the fleas would bite other people, and so on.