27 y/o male with no previous medical history. 5 11 170lbs. symptoms: severe headache , full body aches/pain, vomiting/ nausea , fever ranging from 101.9-103.0F dry non productive cough, and negative test for flu . WBC /CBC normal. Profuse sweats during rest, fever mildly reduced by APAP and immediately returns within a few hours. possible diagnosis?