The word "infection" can denote any presence of a particular pathogen at all (no matter how little) but also is often used in a sense implying a "clinically apparent" infection (in other words, a case of infectious disease). This fact occasionally creates some ambiguity or prompts some usage discussion; to get around this it is common for health professionals to speak of "colonization" (rather than "infection") when they mean that some of the pathogens are present but that no clinically apparent infection (no disease) is present.