Final answer:
An asymptomatic infection is the presence of invading microorganisms without clinical evidence of disease. Not all infections lead to disease; pathogens can exist in the host without manifesting any symptoms or causing tissue damage.
Step-by-step explanation:
The term that describes a physical condition where there is an invasion by microorganisms but no clinical evidence of disease is called asymptomatic infection. Infection occurs when microorganisms, such as bacteria, viruses, fungi, or parasites, enter the body and begin to multiply. If this occurs without causing clinical signs or symptoms, the person harboring the organisms is said to have an asymptomatic infection. Not all infections lead to disease; the presence of pathogens does not necessarily mean the infected individual will experience the detrimental effects commonly associated with the disease, such as tissue damage or a significant immune response. An example of this might be a case where the microbial balance in a particular body part is disrupted, possibly leading to an overgrowth of certain bacteria that usually coexist peacefully with the host, without necessarily triggering an inflammatory response or symptoms.