What Is Infection?
An infection is an invasion and multiplying of pathogenic microbes in the body tissues in which they are not usually present (1). Pathogenic means capable of causing disease. Infection does not always cause a disease.
Definitions of Infection-Related Terms
A colonization is the usual presence of non-pathogenic and even potentially pathogenic microbes on the skin, in the nose, mouth, bowel, penile or vaginal mucosa, as a part of normal human flora, in the amount not harmful for the body – this is not an infection. An example is the presence of Lactobacilus acidophilus bacteria in the colon.
A contamination is the presence of germs which do not multiply, for example, in a contaminated (not infected)wound. Infected or septic wound contains multiplying microbes. Contamination also refers to presence of pathogenic microbes on medical equipment, in the water, food etc.