Surprisingly, having just been the sickest I've been in years, disease is something on my head. Today I figured I'd bring up for discussion how you feel about disease as a plot item. As far as lore goes it's got a lot of backing. There are myths and legends full of some king wasting away from X, Y, or Z terrible disease (often to the plight of the general landscape as well) and needing some hero, or heroes, to bring the cure and restore him to life.
However, there are other ways to use diseases as well. The Black Plague was a notable "plot item" not so much because of who it infected but how many and how lethal it could be. Also in the way it shaped people's reactions not just to outsiders but to each other. Unsurprisingly there is more than a bit of lore detailing the plague as the handiwork of witches who made pacts with demons in order to punish those they saw as being against them.
Still, even with all this lore the idea of disease as a plot item has some issues to it that has made GMs shy away from it. For example, do you need rules for your players to contract the disease? Should that even be a chance or is it something you don't want to even deal with? The mechanical paperwork that can be involved when the fighter should be unable to get out of bed for 2 weeks can be extensive. It can also come across as unfair when you have to stack all those penalties onto the player. Quite simply put: being sick is not very heroic.
So, where do you stand on it in your games? Do you like it? Loathe it? Do you make it possible for your PCs to catch the bug? Sound off in the comments.