[MatthewWilkes]

What if it's mediated by a non-viral disease vector, like a bacterium?

[XorNot]

This also fails to include multicellular alien parasites. They've really left themselves open here.

[arethuza]

Or something like a prion that isn't alive so isn't really an infection?

[Govannon]

Technically viruses are not considered "alive" either