Don't you dare sneeze on me, human

from here

It sounds absurd, I know, but if they can encode malware into a DNA strand then, by the strangeness of computer science, there exists (at least in theory) a computer that would interpret my DNA as a virus, and another (theoretical) computer that would interpret your DNA as a virus, and so on and so forth.

For each sequence of symbols there exists a Turing machine for which that sequence is a virus.