What is the term for the proliferation of infection in the blood?

The correct term for the proliferation of infection in the blood is septicemia. This condition occurs when bacteria enter the bloodstream and multiply, leading to a systemic response that can result in severe health complications, including septic shock. Septicemia is characterized by the presence of viable bacteria in the blood and the body's response to this infection, which can affect organs and contribute to a life-threatening situation.

While bacteremia refers to the presence of bacteria in the bloodstream, it does not necessarily indicate that these bacteria are multiplying or causing a systemic infection. Bacteremia can occur transiently in some medical situations, like during dental procedures, without leading to a severe systemic illness. In contrast, septicemia implies a more serious condition where the infection is actively proliferating and has significant impacts on systemic health.

Lesion refers to an abnormal change in tissue, which can be a result of various diseases but does not specifically describe an infection in the bloodstream. Inflammation is the body's immune response to infection or injury, which can occur locally or systemically but does not directly denote the presence of infection in the blood. Therefore, the term septicemia specifically captures the severity and nature of infection within the blood that can lead to serious health consequences.