Final answer:
The term used to describe the presence of bacteria in the blood is 'Bacteremia.' It involves bacteria present in the bloodstream, and if they are reproducing, this can progress to 'Septicemia,' a more severe condition.
Step-by-step explanation:
The term used to describe the extent of host involvement when there is the presence of bacteria in the blood is Bacteremia. This condition refers to the presence of bacteria in the bloodstream, which is normally sterile.
It's important to distinguish Bacteremia from Septicemia, which is a more severe condition where bacteria are not only present but are also reproducing in the blood.
Septicemia can lead to systemic infections such as sepsis and septic shock. Toxemia is the condition associated with the presence of bacterial toxins in the blood, while Viremia refers to the presence of viruses in the blood.