The advantages to Europe of trade during the long period of history known as "the Middle Ages" were considerable. European and Asian traders, operating mainly along the already-established "Silk Road" routes connecting Asia, the Middle East and Europe, established colonies along those enormously long routes that became important centers of learning as well as trade, and that facilitated the development of diverse cultures. More tangibly, the Europeans reaped enormous dividends from Silk Road trade routes in terms of imports from Asia of spices, silk and other textiles, precious metals like silver and gold, and various agricultural commodities like grapes, cucumbers, carrots, and onions. Agricultural techniques that made irrigation of fields more efficient were imported from Asia, as one of the most significant developments of the age: paper. While Johannes Gutenberg's printing press is appropriately considered one of the most important inventions in history, its practical utility would have pretty limited had the Chinese not invented paper, and had that invention not found its way to Europe through these same trade routes.
Europe benefited enormously from trade with other regions of the world during the Middle Ages. The Chinese, in particular, were very advanced in areas like science, agriculture and development of textiles. All of the above-mentioned imports contributed to Europe's development and prosperity. That particularly deadly bacterial and viral infections similarly made the transit across Eurasia does not diminish the legacy of trade between Europe and Asia.