My son had a fever of 40.3 degrees (104.54 Fahrenheit) a few months ago and the doctors/hospital etc no one knew what was wrong or how to help it, (he kept throwing up any meds given) the ONLY thing that worked was white vinegar!! Rubbed on his hot parts (underarms, back, chest, neck, head etc (NOT private parts) and it went away, honestly worked like a miracle x 100 degrees is still quite low, and it takes a very long time to reach a high temp like 104. It took a whole three days for my sons temp to get to 104
That's considered a low-grade fever. But under 3 months a doctor should be contacted. Anything over 3 months can be managed with medication ☺️