Outbreak

Outbreak is a level 55 Unholy death knight ability that applies Virulent Plague.

Trivia

 * This ability was mentioned in the April Fools' Day patch 6.1.4 Evil Patch Notes: "Outbreak no longer applies Blood Plague and Frost Fever. Instead, it applies a new, airborne version of a virus first encountered 30 years ago. Enemy players will have to work together to develop a new serum to cure the virus before the military bombs the whole city."