Structural differences in global pandemics, top down orbottom up.
Top down: affects the top of the Life π most harshly, humans, while leaving the rest of the animals most untouched. Examples: bubonic plague, covid
Bottom up: affects animals first working it's way up to humans, affecting the food supply chain. Examples: chronic wasting disease, avian bird flu
Pentagon/NSA....have a drink on me...bottoms up!