Final answer:
Toxemia refers to the extent of host involvement when toxins are present in the blood. It occurs when toxins produced by bacteria enter the bloodstream and can lead to serious complications.
Step-by-step explanation:
The condition that refers to the extent of host involvement when toxins are present in the blood is toxemia. Toxemia occurs when toxins produced by bacteria enter the bloodstream and can lead to serious complications. It is important to note that toxemia is different from septicemia, which is when bacteria are both present and multiplying in the blood.