
There could be several diseases and several random objects that can be used for cures, some for one disease and some that have a small effect on all.
Diseases could include:
Malaria (Can be contracted in a swamp during a heating period, usually fatal unless treated with modern medicine, so in the era we're in would most likely be fatal, ice in a bag could help... now we just need seasons or temperature and rivers to freeze over)
Random Sickness (You know, like a common cold, runny nose and whatnot)
Food Poisoning (Could be related to a "hurt" food event)
Bird Flu (You know, the epidemic that killed 50% of people infected several years ago?)
Sleeping Sickness (Causes the player to randomly fall to the ground asleep from being too tired and also causes the player to barely reduce travel weariness when sleeping in a bed at night)
Diarrhea (Causes stamina to drop dramatically from dehydration, could be linked if there is a "Bathroom" need in the future)
Heat Stroke (Related to temperature, like in Malaria)