How Can High Fever Along With Appetite Loss And Fatigue Be Treated?

My 77-year-old husband has had a fever for two days, 102 degrees maximum. His appetite is lousy and he s tired. He doesn t cough much, but once I saw a yellow glob come up when he did cough. (Not sure if it came from postnasal drip or lungs). No runny nose, sore throat, hacking cough, or other cold symptoms. But four months ago he had a similar episode and since then he s had a kind of chronic cough (he calls it a tickle and it s not very productive) that never went away. No muscle aches or soreness at this time, and he is normally very active and healthy. Pneumonia? Thank you!