Illness

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Illness

Maladies and strange diseases may affect adventurers in far-off lands...or even at home. The search for a cure – whether for the Princess' wasting disease, an alien plague, or a terrorist's bioweapon – is a wonderful plot device. The invention of diseases is an excellent opportunity for the GM to exercise a morbid sort of creativity.

Magical or technological items, the Resistant advantage, and high HT can all protect you from disease. Risks are greatest in warm, moist areas. If you catch something, you won't know until the symptoms start to show...the GM makes your roll to avoid it!

Disease

Most diseases are caused by microorganisms and spread by infected people or animals – but some have other causes!

News about disease-ridden areas travels fast; a successful Current Affairs roll can alert adventurers to the presence of disease in a region. Spotting locals suffering from symptoms requires a Perception-based Diagnosis or Physician roll. And in an area where animals are carrying a disease that people can catch, investigators would need to examine an infected specimen and make a successful Veterinary roll to realize the danger.

Contagion

If you enter a disease-ridden area or encounter a disease carrier, make a HT roll at the end of the day to resist the disease. On a failure, you catch the disease! Modifiers to this roll include the disease's basic virulence modifier and the least advantageous applicable modifier from this list:

Avoided all contact with possible victims: +4.
Entered dwelling or shop of victim: +3.
Spoke with victim at close quarters: +2.
Touched victim briefly: +1.
Used victim's clothes, blankets, etc.: +0.
Ate victim's cooked flesh (animal, we hope!): +0.
Ate victim's raw flesh (ditto!!): -1.
Prolonged contact with living victim: -2.
Kissing or other intimate contact with victim: -3.

Proper precautions – masks, antiseptics, etc. – provide a bonus to those who know and understand them. The GM should consider limiting such measures to PCs from cultures that understand the germ theory of disease (late TL5).

Defining a Disease

Diseases are defined in much the same way as poisons (see Poison). For each disease the PCs encounter, the GM should specify:

Vector: How the disease spreads. Diseases are generally blood, contact, digestive, or respiratory agents. These terms mean just what they do for poisons; see Delivery.
Resistance Roll: The HT roll to avoid the disease. Anyone exposed must roll, possibly at a penalty. Most diseases allow a roll at HT to HT-6. The means of exposure can modify this roll; see Contagion. On a success, the victim does not contract the disease. On a failure, he does, but he gets further rolls – once per "cycle" – to throw off the disease.
Delay: This is the incubation period – the time between initial exposure to the disease and the appearance of the first symptoms in those who fail to resist. This is 24 hours for a "generic" disease, but can vary considerably for real-life diseases.
Damage: The disease's effects in game terms. This is typically 1 point of toxic damage, but it might be higher – up to 1d – for virulent diseases. DR does not protect against disease! Symptoms (fever, sneezing, coughing, spots, rash, etc.) appear after the subject starts to suffer injury. Injury from disease will not heal naturally until the victim makes his HT roll to recover!
Cycles: Like a cyclic poison, a disease damages its victim at regular intervals until he makes a HT roll or a maximum number of cycles passes. The "default" interval between HT rolls is one day. The number of cycles varies with the deadliness of the disease; for instance, a potentially fatal disease might only inflict 1 HP per cycle but endure for 20-30 cycles.
Symptoms: A disease can cause attribute penalties, temporary disadvantages, etc. after the victim loses a specified fraction (typically 1/3, 1/2, 2/3, or all) of his HP to it.
Contagion: Some diseases are mildly or highly contagious – although sometimes not until after the incubation period.

The combination of resistance roll, damage, and cycles determines "deadliness." By carefully selecting these statistics, the GM can distinguish between a virulent but mild flu that ends in a day or two (24-hour delay, HT-2, 1 point of toxic damage, 12-hour interval, six cycles) and a slower but usually fatal disease (72-hour delay, HT-5, 1 point of toxic damage, daily interval, 30 cycles).

Diagnosis

Once the symptoms of a disease become apparent, identification requires a successful roll against Diagnosis or Expert Skill (Epidemiology) – or Veterinary, for an animal illness. This cannot identify a totally new illness, but a good roll might give enough information to allow treatment.

Treatment

Appropriate remedies – herbs, drugs, etc. – can provide a bonus to the cyclic HT rolls to shake off certain diseases. At TL6+, antibiotics (e.g., penicillin) give +3 to recover from most bacterial diseases. At any TL, a physician's care provides the same bonuses to recover from disease that it gives to recover from injuries (see Medical Care).

However, some diseases are drug-resistant, in which case ordinary medicine gives no bonus. At TL7+, drug treatments can often mitigate the effects of such illnesses – usually by reducing damage or lengthening interval – but these aren't cures. Radiation treatment, gene therapy, nanotech, magic, and psi might still work, however.

Immunity and Susceptibility

Differential Susceptibility: Members of a given ethnicity, sex, or race may be more or less susceptible to a particular disease. For instance, the GM might decide that dwarves are immune to the Purple Shakes, and that elves get +2 on their HT rolls against it...but that the mortality rate among male giants is 100% unless they are treated within two days. A successful Diagnosis or Physician roll reveals differential susceptibility, if applicable.
Natural Immunity: Some individuals are simply immune to a specific disease. If the GM rolls a 3 or 4 for your first attempt to resist a disease, you are immune! He should note this fact and not tell you – under normal circumstances, you have no real way of knowing about your immunity.
Acquired Immunity: Anyone who survives a given disease may be immune in the future. This depends on the illness. You only catch measles once, for instance – but mumps can come back over and over.
Vaccination: Vaccination won't cure disease, but it provides almost certain immunity. At TL5, vaccines exist for a few diseases – notably smallpox – but aren't widespread. At TL6+, new vaccines appear constantly, and most can be stored for long periods of time, like other medicines. Developing a new vaccine is difficult and time-consuming; use the rules under New Inventions, rolling against Bioengineering skill. At TL10+, exotic treatments (e.g., nanomachine colonies) can give individuals or entire societies the Resistant to Disease advantage.

Infection

A microorganism that attacks open wounds may cause an "infection." Infections are possible anywhere, but some places (especially jungles) may harbor especially severe forms of infection.

Open wounds treated with antibiotics (TL6+) never become infected except on a critically failed First Aid or Physician roll. People wounded under less-than-clean circumstances (GM's decision) and who do not receive treatment must make a HT+3 roll, modified as follows:

Ordinary "clean" dirt in wound: +0.
Dung or other infected matter in wound: -2.
Locale harbors a special infection: -3.

These modifiers are cumulative, and replace those listed under Contagion.

On a failure, the wound is infected. Treat this as any other disease. A typical infection requires a daily HT roll, modified as above, with failure indicating the loss of 1 HP. Most infections progress until the victim either makes a HT roll, ending the infection, or takes so much injury that he dies.

Treatment with antibiotics (TL6+) gives +3 to HT rolls. This usually halts the infection before serious injury can occur.

If drugs are unavailable, or if the patient doesn't respond, a surgeon can cut out the infected tissue if the injury from infection hasn't progressed beyond a certain point. On the head or torso, this limit is the patient's HP/2. On a limb or extremity, it is the amount of injury required to cripple the body part. Surgery cannot help infections more severe than this.

The surgeon must make a Surgery roll. This inflicts 2d of injury to the head or torso, or amputates a limb or extremity. On a success, it cures the infection. On a failure, damage or amputation occurs but the patient remains infected.