Sewer plague

Sewer plague was a colloquial term for common diseases frequently encountered in sewers, swamps, dumps, stagnant waters, and other filthy or fetid places.

Acquisition
Because "sewer plague" was a general term, it did not necessarily refer to diseases with a single vector of infection. Some sewer plagues were spread by bites from sewer-dwelling creatures such as rats, otyughs, or the undead. In other cases, mere exposure to contaminated offal, open sewage, or other waste for at least one minute was sufficient to risk infection. Individuals who were injured had a much greater risk of contracting sewer plagues while in contaminated environments.

An individual exposed to and infected with a sewer plague would begin showing symptoms within four days.

Effects
Sufferers of sewer plagues generally experienced cramping and fatigue, which could progress into extreme exhaustion, interference with the body's natural rest and recovery processes, and ultimately even death.

Treatment
Healthy individuals could fight off the disease naturally.

History
As of the late 15 century DR, sewer plagues were notable in the sewers of Waterdeep and the sewers of Mulmaster.