Pathogenicity is the ability of an organism to cause disease in another organism. It is often used interchangeably with the term "virulence", although some authors prefer to reserve the latter term for descriptions of the relative degree of damage done by a pathogen. Pathogens are infectious agents that cause disease and include viruses, bacteria, fungi, protozoa and higher parasites. The agents responsible for the CJD and BSE are also pathogenic. Virulence is a term used to refer to either the relative pathogenicity or the relative ability to do damage to the host of an infectious agent. ... Jump to: navigation, search A pathogen (literally birth of pain from the Greek παθογένεια) is a biological agent that can cause disease to its host. ... A common alternate meaning of virus is computer virus. ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... Divisions Chytridiomycota Zygomycota Ascomycota Basidiomycota The Fungi (singular: fungus) are a large group of organisms ranked as a kingdom within the Domain Eukaryota. ... Protozoa (in Greek protos = first and zoon = animal) are single-celled eukaryotes (organisms with nuclei) that show some characteristics usually associated with animals, most notably mobility and heterotrophy. ... A parasite is an organism that lives in or on the living tissue of a host organism at the expense of it. ... CJD can mean: Creutzfeldt-Jakob disease chronological Julian day This page concerning a three-letter acronym or abbreviation is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... Bombay Stock Exchange Bovine spongiform encephalopathy ...