Disease

A disease was a detrimental medical condition that was not an injury.

Description
A disease could be transmitted in various ways: injury, ingestion, inhalation, mere contact, etc. Some were also caused by parasites. Creatures exposed to a disease ran the risk of becoming infected unless their immune system could fight it off. If the exposed individual lacked a strong enough constitution, the disease took hold. After an incubation period, the disease showed its symptoms, which persisted until the host was cured of the disease or died of it.

Contagious diseases spread readily in heavily or densely populated cities throughout Toril&mdash;where filthy sewers provided ideal conditions for a variety of maladies to thrive&mdash;as well as along heavily trafficked trade routes. Both ordinary disease as well as parasitic infections were generally more common in hotter and wetter climates and in filthy or crowded conditions. When new or unknown diseases arose, most often this happened in rural or frontier settlements where the people encountered previously unknown afflictions while interacting with remote insects, beasts, and plants.

There was a generally important distinction between diseases which were "natural" and those which were "supernatural" or otherwise magical in origin. Natural diseases were acquired by mundane means, so even the most exotic of them could be treated (although perhaps not cured) with traditional or nonmagical care. Meanwhile, supernatural diseases were generally incurable with natural or normal medical efforts. Such magical diseases were often spread by magical creatures, such as lycanthropes or mummies.

Diseases in Society
Whenever a disease struck in Faerûn, or wherever folk feared that it would, they prayed and made offerings to the goddess Talona, the Mistress of Disease and Mother of Plagues. A common practice was to drip three drops of blood or tears&mdash;in homage to her holy symbol of three droplets in a triangle pattern&mdash;into or onto something or someone that was diseased, such as the mouth of a sick person, a tainted well, or blighted crops. For many folk, such acts of observance was seen as an obligation to placate the capricious goddess rather than a desire to venerate her. The Church of Talona had a tenuous relationship with most other folk of Faerûn: on one hand, they were blessed with an immunity to disease, which made them valued doctors and healers in times of sickness. On the other hand, they were known to spread sickness themselves, especially to those they felt had disrespected their goddess, and this made them generally feared and disliked. Open worship of Talona was even banned in some places, such as in Waterdeep during the late 15 century DR.

When it came to practical means of preventing or treating diseases, most people in Faerûn had no real medical knowledge and therefore relied on past experience, either re-using methods that had helped themselves or close associates in the past or seeking the counsel of elders and the like. In general, folk had at least some shared understanding about how certain diseases were transmitted, and a baseline agreement about the importance of cleanliness, rest, care, and the use of purgatives to treat illness. Beyond this, however, there were many disagreements about treatment methods, which was the case for at least two main reasons: first, there was the aforementioned reliance on personal experience&mdash;which could differ between individuals or groups&mdash;and second, there was false information that was intentionally spread. While some falsehoods were spread by evil factions with the goal of causing strife, such as by followers of Talona, other times they were spread by otherwise benevolent factions or churches in an effort to exert influence or to secure more coin for healing services.

The most well-known diseases in Faerûn included the so-called Five Fevers and Three Plagues.

Plagues
On Toril, widespread plagues were mostly a problem of the past by the 14 century DR. The main reason for this was that diseases turned into widespread plagues when a population had never encountered them before, and most people were the descendants of survivors of plagues&mdash;and had inherited immunities from their ancestors&mdash;or had been exposed to various diseases since childhood and therefore developed immunities. Toril also had a long history of interspecies intermingling and crossbreeding, which boosted the population's resistance to disease.

Another reason why plagues were contained was that preventive measures were taken priesthoods and rulers. This was done either through official enforcement, by secretly mixing medical substances into food and water, or collective action to contain outbreaks. For example, churches could band together stop a deadly plague in its tracks with few casualties, as happened with an outbreak of spotted plague in Iriaebor in 1367 DR. People who were obviously afflicted with a terrible disease might also simply be killed as a precaution, at least in frontier regions. On the Sea of Fallen Stars, it was a widespread practice that a ship carrying plague would signal this by smearing blood or red paint on their sails. In response, other vessels would provide clerical healing if available, otherwise they were advised to burn the plague ship to the waterline with fire arrows or spells.

The exception to the rule that plagues were no longer a problem was the goddess Talona. Whenever she felt that her power or faith was waning, she was prone to inflict a plague on the land or at least on a city that she felt had slighted her church.

Common Diseases
The most common or well-known diseases in Faerûn were:

Other notable diseases included:

Regional Diseases
Regional diseases included:

Unique Diseases
Notable unique diseases included:

Non-Humanoid Diseases
Diseases affecting creatures other than humanoids included: