Thank for asking to HCM
I really appreciate your concern, looking to history given here I could say that if the routine blood work does not show anything then some special test has to be done like blood culture
test, widal test
, imaging test, urine test, in short all the tests which are necessary and being perfume to find out the cause of fever
if the temperature is high then the cause of this need to be found out any how, treating the symptoms is not advisable, take care and have a nice day.