Disease ecology

thumb|upright=1.35|A fish parasite, the isopod [[Cymothoa exigua, replacing the tongue of a Lithognathus]]

A zoonosis (; : zoonoses) or zoonotic disease is an infectious disease of humans caused by a pathogen (an infectious agent, such as a virus, bacterium, parasite, fungi or prion) which can jump from a non-human animal to a human. When humans infect non-humans, it is called reverse zoonosis or anthroponosis.

organism that harbors another organism; organism whose resources are used by another organism then called parasite

metric in epidemiology showing average measure of a pathogen’s infectiousness

application of geographical methods to the study of health and disease

species of mammal

overview of the relationship between climate change and infectious diseases

thumb|Colonies of the bacterial sapronosis Legionella pneumophila A sapronosis is an infectious disease caused by an organism that is able to live and reproduce in the soil or an other abiotic environment, and infects a living host directly from that environment. One widely-known example of a sapronosis is Legionnaires' disease. Approximately a third of all known disease organisms are sapronoses. Almost all fungal infections are sapronoses, but there are no known sapronotic viruses.