One of the most insidious threats in this era is disease. Malaria, yellow fever, the black plague and syphilis are widespread problems, and characters exposed to these epidemics must have the fortitude to resist them. And if they catch them, they need the durability to survive them.
In a game of swashbuckling action, disease is rarely an issue for the player characters. The introduction of illness should serve dramatic purpose and heighten the tension in the adventure. It should not simply be introduced on a whim.
When exposed to a disease, you must make an Endurance (Toughness) roll against the disease’s Threat Rating. If you roll the required number of successes, you resist the disease. Otherwise, you suffer the disease’s effects.
Unlike most hazards, disease is broken down into a number of different factors:
Threat Rating: as with all other hazards, this rating is used to determine the potency of the disease. It sets the difficulty to resist exposure and determines the damage the disease does at each interval.
Afflicted Ability: Unlike most hazards, diseases do not cause physical damage to your Health Track. Instead, it directly affects your Ability scores. Most diseases affect only one Ability, but some of the more potent diseases might affect two. Once you suffer damage to any one Ability, you become Exhausted (see Limiting Conditions, pg 191). If an Ability is reduced to 0, you become Unconcious until the following interval (see below). At this point the character is at risk of death. On the next interval, if you fail your Endurance roll, your character dies.
Onset: How long after exposure it takes for symptoms to manifest in the victim.
Intervals: You suffer the effects of the disease each interval. Also, you may make a new Endurance (Toughness) roll at each intervals to resist, or even overcome, the disease. Each interval, you must make an Endurance (Toughness) roll against the disease’s Threat Rating. Each success beyond those needed reduces the harm caused by the disease by 1 point. If the harm is reduced to less than zero, you have overcome the disease and will begin to recover normally. A Heal/Medicine (Reason) roll vs. the Threat Rating of the diseases grants you a +1d bonus for each additional success.

Disease Table
Threat Ability
Rating Damage
1 0
2 1d
3 2d
4 2d+1
5 3d+1

Sample Diseases
Disease TR Ability Onset Interval
Black Plague ? Toughness 1 day Days
Cholera ? Toughness 1–3 days Days
Dysentery ? Health 1-3 days Days
Leprosy ? ? 2-4 wks Weeks
Malaria ? Str/Tou 1-3 days Days
Tuberculosis ? Str/Tou 1-4 days Days
Typhoid Fever ? Strength 1-3 days Days