[run] a (temperature|fever)

to have an elevated body temperature, often as a symptom of an illness or infection

She couldn't go to school because she was running a fever and needed rest.
The child was running a temperature, so the parents gave them fever-reducing medication.
If you run a high fever, it's advisable to consult a healthcare professional.
Running a temperature can be a sign that your body is fighting off an infection.
It's essential to stay hydrated when you run a fever to avoid dehydration.