One sunny afternoon, Tommy and Ellie sat in front of the fireplace as Grandpa Henry started to tell another new story: "Long ago, there had been some terrible sickness then, called the Bubonic Plague or more popularly Black Death, that originally came from a very, very far away place called China.
"The plague spread from rats to humans," Grandpa explained. "You see, rats carried tiny creatures called fleas, and those fleas were infected with a dangerous germ. When the fleas bit people, they spread the disease."Tommy's eyes grew wide. "Rats? How did the disease travel from China?

    "Well, Tommy," said Ellie, "the Plague didn't stay in China. It traveled along trade routes, which were paths used by merchants to buy and sell things. The traders moved the rats and fleas to many places, like Europe, Africa, and Asia."

Grandpa added, "It reached Europe in 1347 when a ship carrying goods docked in the port of Italy. Before long, the disease spread to other countries in Europe, like France, England, and Spain. The plague spread quickly because people didn't know how to stop it."

    Tommy asked, "What happens to people who get the plague?"

Ellie replied, "People who got the plague felt very sick. First, they had fever and headaches. Then, their skin turned dark and swollen. These big, painful bumps were called buboes (that’s where the name ‘Bubonic Plague’ came from)."

Grandpa Henry shook his head sadly. "Many people didn't survive. The plague killed a lot of people very quickly."