Warhammer Armies: Beasts of Chaos (2003), p8 — The Four Great Gods of Chaos

Nurgle is the Great Lord of Decay who presides over physical corruption and morbidity. Disease and putrefaction attract him like a fly to a rotted corpse. It is the lives of lepers and the sorrows of the sick that fascinate him most. For his amusement he devises foul contagions which he inflicts upon the world. Many of the most horrible diseases are the creations of Nurgle, including the nauseating Red Pox and, most disgusting of all, Nurgle's Rot.