Malaise Damage
Malaise is a sapping or mind and body. It can come from or with disease, lack of rest, poor nutrition, and other such things. Malaise can accumulate in a character. It cannot kill in and of itself, unless specified by its source. All Malaise vanishes after a specific period of time where the character does nothing but rest, or each measure of Malaise may have its own alleviation (treatment and/or time interval) in which it is negated.
Base Healing Rate/Recovery: Malaise Damage is normally healed at the base rate of 1 during a Short Rest, and all accumulated without specific alleviation at the end of a Long Rest.
iCore™D20 Damage Mechanics
All Malaise vanishes after a Long Rest. A character can accumulate Malaise equal to their Constitution modifier (or zero). Each Malaise above this threshold will impose a first general Illness (Disease), after after that a [cumulative] level of Exhaustion. This exhaustion persists until a Long Rest or until the circumstances of the source say so.