prejume fu'ivla

x1 displays viral/contagious aspect, spreading through population/network/geography/vel sim x2 or the ability to do so.

x1 is infectious/a contagion/has tendency to spread, in the broadest sense. Infectious laughter, computer viruses, cancer, viral memes (in the original and more modern senses of the word), as well as biological contagions (bacterial, viral, and fungal infections, etc.). See also: "virme".

In notes:

x1 gives/exchanges/spreads contagion x2 to x3 via means x4; x1 infects x3 with x2.
x1 is a micro├Ârganism, virus, protein, spore, pathogen, or other such substance which causes or is intimately associated with disease(s)/symptoms x2.