people have been trading for a long time. the modern point-to-point connections didn't exist, obviously, but east asia and western europe have been indirectly c

people have been trading for a long time. the modern point-to-point connections didn't exist, obviously, but east asia and western europe have been indirectly connected through trade routes since ancient times [0]. as long as the disease wasn't virulent enough to kill most hosts in a single leg of transit, it could be spread across all of asia and europe. the world-wide spread would be slower, but intra-community spread would probably be even faster due to the lower standards of sanitation and medical understanding. a truly global pandemic probably wouldn't have been possible with the lack of connectivity between eurasia and the americas. [0] https://en.wikipedia.org/wiki/Silk_Road https://en.wikipedia.org/wiki/Silk_Road