A method for hyperthermic treatment of body fluid includes diverting at least a portion of a body fluid through a body fluid inlet from a body. A viral load of a pathogen is measured in the body fluid, and a target treatment temperature is determined based on the measured viral load. The body fluid is heated to the target treatment temperature to decrease the viral load in the body fluid. The body fluid is returned to the body after hyperthermic treating through a body fluid outlet. Hyperthermic treating of the body fluid is repeated with another portion of body fluid diverted through the hyperthermic treatment assembly.
