Thorough history including ROS, PMH/PSH, immunizations, including from childhood
Fever curve (holding antipyretics); look at trend/pattern. Less likely to mount fever if: ESRD/ESLD, extremes of age, protein calorie malnutrition, immunosupp., steroid use.
Exposures: travel, occupation/hobbies, animals, sexual contacts, TB. Consider geography, season, and incubation time in relation to exposures.
Physical exam: look for thrush, dental caries; full eye exam; cardiac murmurs; HSM; abd tenderness; rash/skin lesions; LAN; synovitis; complete neuro exam