Husband has fever hovering in 100-100.5 range, itchy not sore throat, no drainage, no headache but some body ache fatigue. Is this the flu?

May or may not be. The way i treat people is if in doubt and there's no real big detriment to treatment, and most of all if that person benefits from a treatment, i would treat it. Of course, if you go to the er or urgent care, they may be able to do a quick test for the flu and tell you.