Every player has a chance to catch disease during the game and then suffer from its negative effects for a while.
The chance to get sick is 3% every minute +0.3 per minute in the casual mode and 6% +0.6% per minute in Hard Mode. Perk Healthy reduces the chance by 50%. Every time you survive (or heal) a disease, the chance of getting the next one is reduced; the total chance is divided by 1 + the number of times you have been sick.
The duration of the disease is random, it can be from 5 to 15 minutes, however your Wickedness has an effect on it. Each 33 points of it reduce or increase the duration by 1 minute.
In addition to that, an active disease blocks all passive regeneration (like from the perks Troll, Passive Heal, Entrenching, Rage, etc.), but it does not block active healing (like from the perks Paladin, Go Green, Vampire, etc.). The last negative effect of the disease is that it reduces hero health by 10% of the maximum value every minute (applied at the 13th second every minute), which eventually can kill the hero.
To heal the disease you can simply use heal consumable (First Aid Kit). It doesn't heal injuries, but it does heal diseases. Some perks like Doctor, Alteration, Phoenix, and Cup Of Tea heal the disease as well.
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