Curses and Diseases

I remember that original FRPG. Lost in the game master’s book was a rule that said that every player character had a chance of catching a disease every month (and a chance of parasitic infestation). I think it started at 1% and went up depending on conditions. I kind of liked that rule; thought it added flavor. The problem is, I remain curious how diseases run in a fantasy era. Oh sure, the priests can cure diseases, but I don’t think that should be a 100% chance. (See this post) So I’ve been doing a little research on diseases and trying to put them into game rules. I also want them to all be a little different, not just have each one reduce Endurance. But another thought came up and I’ve been developing the two together. What are curses? I’m going to make curses magical diseases. Now many of the curses will be identical to the diseases, except that you can only cure them through magic. (You can get over a real cold, but not a cursed cold.) So now I’ve given myself the task of not only figuring out what diseases will do, but of assigning spell like stats to them as well. There will be some wildly magical curses too. Stuff like every time you sneeze, you turn blue. That would be a fun curse! A thought has come up in all of this though: Can you curse someone with lycanthrope or vampirism? I think so! I think the curse would be a pretty powerful spell, but I think so. Pretty nasty thing to do to somebody, but pretty cool too. I’m thinking that killing the curser (OK, “witch”) will remove the curse. That makes curses better mission starters. The prince insulted an old hag and now every time he sneezes he turns blue. Go capture the hag and get her to remove the curse, even if you have to kill her. OK, not the most original, but not too bad for a little filler mission. I’m still working on developing curses that will reduce luck or something like that. The game balance on something like that could be very difficult, otherwise the curse becomes incredibly powerful. Any ideas?