Ever since 9/11 my sinuses have been a total mess - I mean, admittedly, they've sort of been not great for a while, but after "the unpleasantness downtown" spewed a toxic chemical stew into the air above New York, I started getting sick every 3 months or so. For a while I thought I was better, but it came back with a vengence this past year (probably a function of stress and not taking care of myself).
Work becomes a blur, and it's all that I can do just to do the barest minimum. I fret myself into disease and only when I'm truly good and sick do I realize, "Oh! that's why I've been such a jerk lately: I'm getting sick!"