I was sad to find out

As the trade of goods and cultures expanded, so the trade of disease increased as well. These diseases followed the same pattern of trade, and even extending to populations that were isolated and unprepared to deal with unfamiliar consequences. These diseases did not discriminate amongst the rich and poor, and had tremendous effects. Some of the early examples of trade of diseases involved the Greek city of Athens, between 430-429 b.c.e. which began in Greece via seaborne trade from Egypt, killing about 25 percent of its army and weakening the city state (p.290).

Smallpox and measles greatly affected the Roman empire and the Han dynasty through the Silk Road as they came in contact all across Eurasia as well. As a result of these diseases, these empires collapsed politically. Paradoxically these disasters strengthen the appeal of Christianity in Europe and Buddhism in China as both offered compassion in the face of enormous suffering (p. 290).

 Between 534 and 750 c.e. The bubonic plague invaded the coastal areas of the Mediterranean Sea as the black rats that brought the disease arrived via the seaborne trade with India where they originally lived. Their effect was catastrophic: Constantinople, the capital city of Byzantine Empire, lost thousands of people daily, during a forty day period in 534 c.e. Based on records of contemporary historians.

The Mongol empire also had its share of spread of the Black Death, that extended from China to Europe. However, as the Western Hemisphere became colonized by Europeans in the 1500´s, they were in great disadvantage over some of these diseases as they had not domesticated animals, they did have as much interaction with big populations, and were isolated from the Eastern Hemisphere.