I contracted some kind of stomach bug in south america that I had for about 5 years afterwards - in that I couldn't have certain foods/drinks without becoming really ill. However it didn't make me that ill when I was actually travelling other than constant vomiting and diahorrea. No aches or shivers or anything.
I suppose the worst thing that happened to me was that I had a rare congenital deformity which meant I lost the use of my arms for 5 - 6 years between the ages of 18 - 25 (it took them that long to diagnose and treat it). I was in pain for 95% of the time, had no grip or strength in my arms and hands, and it pretty much scuppered all of my career plans, ambitions and hobbies, and changed the course of my life permanently. I often wonder what would have happened to me had it not been for that.