What is the definition of Universe Infection?

An "universe infection" is like when a spaceship from another galaxy decides to crash-land on Earth, but instead of just causing a minor inconvenience like a broken air filter, it brings along an entire ecosystem of alien bacteria, fungi, and whatever else it's brought with it. It's like the cosmic equivalent of a zombie outbreak, but instead of undead humans, it's overrun by the microscopic hordes of life that live in harmony with other extraterrestrial species.

---

Here's an unsettling example sentence: "The universe infection hit Earth like a bad cosmic prankster, leaving behind a trail of bioluminescent slime and a whole lotta existential dread in the wake of our cosmic apocalypse."