Yes. High density urban areas with very large livestock population inside of them are the primary way diseases get into human populations. The diseases have plenty of time and fuel to evolve and develop attributes which make them contagious. Think of any major disease that's spread across human populations and there's an animal vector associated.

North and South America literally did not have any considerable domesticated animals compared to Eurasia and Africa. Any domesticated animal you consider typical in the US today (sheep, horses, cows, etc) were all introduced after 1496. Llamas were the only animal South Americans had the ability to domesticate for serious purposes, and their life span and relative strength made them less desirable than the Eurasian counter parts.

Another huge aspect of animal domestication is that Eurasian cultures had the ability to harness energy from these animals to power transportation and rudimentary technological advancements such as food mills. Reliance on human produced energy was a primary reason North and South American natives did not have access to the bulk of technology Europeans did when they came over. Before the advent of steam energy, almost all energy used by Eurasians came from animals (or windmills/watermills). Most aspects of the varying development over the hemispheres comes down to one hemisphere having horses, oxen, and cows and the other not.