Disease

Diseases can generally attack your ability scores over time, diminishing your fighting ability to leave you helpless. They may also leave you blinded.

Diseases differ from curses in that they are often the effect of a physical act or touch.

When you are exposed to a disease, your character makes a saving throw vs. the disease's difficulty class. Your character will have a modifier to this saving throw derived from your class levels and your race. Potentially modified by what enhancements and feats you have taken, as well as whatever buffs have been cast on you, and what equipment you are wearing. Disease Immunity effects on items make you completely immune to disease.

Mummy Rot is both disease and curse. It will kill the character unless both effects are removed and in the right order.

Halflings are resistant against disease, while the Warforged are immune.

Two classes are immune to disease at specific levels: Paladins (level 3, with granted Divine Health feat) and Monks (level 5, with granted Purity of Body feat).

Aside from saving against the affliction, diseases can be removed by the Remove Disease spell, potion, or the Monk spell-like ability, The Receptive Earth.

List of Diseases
Diseases