I, for one, believe that one of the causes of EP is bacteria or pathogen(s) incubating within the genito-urinary tract. I know what you mean about the low-grade fever because I feel that way at least 3 x week. My temperature registers fine...but my body feels like crap! Recently, I had a brief bout with a cold accompanied with sore throat. Perhaps, these side effects are caused by the infection within my system.