Once had the flu with a fever of 106-107(almost 42c)...I was taken to the hospital and the doctor literally threw me into an ice bath... I was crying and he said "I'm sorry but you will be dead soon unless we drop that fever"
I had to continue taking ice baths at home because the fever kept creeping back up to that range. They're not fun...
Last time I had intense fever dream was when I was a child. For some reason I never had another. As an adult, I would get sick with occasional high temperature but I would wake up immediately as soon as I sweat heavily.