The earliest symptoms of HACE and HAPE, for even the most experienced climber, can be confused with the usual discomforts of acclimatization, and a misunderstanding can be fatal.
Anatoli Boukreev, The Climb, page 78
A simple, eloquent statement.
Bob R has an excellent documentation of this long-term, overlooked early signs of HAPE in an account of a Denali expedition. One of the participants became lethargic over time and I believe that he even had a slight cough; the others misinterpreted it as failed conditioning (if I remember correctly)
Our resident Geek might bee able to dig up this most excellent article somewhere in our archives.
As an afterthought, I will mention that I just got over my 5th(!) episode of pneumonia, but yet, I
still missed the early signs. Our lost comrades did not have 5x to blunder.
