<s>[INST] hi, my son is 5 yr old just start Kindergarten for 2.5 weeks. Since yesterday, he complaints about tummy ache and has a fever of 102F. Loss of appetite and fatigue. I gave him Ibuprofen a couple time, fever is able to come down to 99-100F. Is it stomach flu or just influenza? [/INST] Hi...by what you quote it looks like viral illness or viral fever. Fever of few days without any localizing signs could as well a viral illness. Usually rather than fever, what is more important is the activity of the child, in between 2 fever episodes on the same day. If the kid is active and playing around when there is no fever, it is probably viral illness and it doesn't require antibiotics at all. Once viral fever comes it will there for 4-7 days. So do not worry about duration if the kid is active. Regards -  </s>