I reread with interest the excellent and varied posts on the Top 10 Trip Busters.  I guess I've been lucky so far.  I can't recall any trip that was a "bust" due to death, injury, loss of stuff, or even someone in the party being a big-time turdball.  

But Sparatan2's well written and accurate words about pre-existing medical conditions got me wondering.  I can't recall ever getting sick on a trip in the past 37 years.  Never once.  Never giardia, the flu, migraines, etc.  Just a few cuts, bruises, and strains now and then.  Closest I ever came was last summer as I rolled into Duluth to spend the night before the next day's launch.  Came down with acute pneumonia that delayed the trip for a couple weeks.  (thx again Westwood for your wonderful hospitality during that ordeal).  

Has anyone gotten so sick during a trip you had to actually "bust" your trip and come out early?  If so, what happened?