Show Me A Motion
Let's start with an old favourite. Amoebic dysentery can be caused by eating contaminated food or drinking contaminated water, and the fear of this disease should be enough to persuade drinkers to boil their water first.
Amoebic Dysentry: Amoebic dysentery is an intestinal infection caused by the amoeba Entamoeba histolytica. Its symptoms include violent stomach cramps, diarrhoea, aching muscles and general fatigue.
Infection DC: Ingestion 15
Incubation: 2d6 days
Damage: 1d3 Dex, 1d4 Con
Additional Effects: The character must make a DC 15 Fortitude save for each day she is infected, or be fatigued until she receives eight hours of complete rest.
The disease is also a great way of slowing the PCs down if you feel they're tearing across the map too quickly, and for frustrating them if you happen to get off on the players' frustration.