Pathogenic, in simplest terms, is the mechanism by which a pathogen (disease causing microorganism, such as bacteria, virus, etc.) infects someone. It includes the various stages of the disease, starting from initial development and ending with end of the disease. Depending on the pathogen and the disease, there can be several stages of the pathogenesis. It is of significance to medical practitioners, to understand the disease and what stage it is at. Such information is useful for prescribing a treatment to the patient. It is also used by pharmaceutical companies to develop cure for the disease, as it can be stalled at various stages of development. It can be of various types, including bacterial pathogenesis (when bacterial pathogens cause a disease), viral pathogenesis (mechanism by which a virus causes disease), etc.
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