Editing Parasitism (section)

==== Directly transmitted ====

<!--[[File:Schistosoma mansoni2.jpg|thumb|''[[Schistosoma mansoni]]'' an obligate directly-transmitted [[endoparasite]], causes [[schistosomiasis]] (snail fever)]]-->
[[File:Male human head louse.jpg|thumb|[[Pediculus humanus capitis|Human head-lice]] are directly transmitted [[Obligate parasite|obligate]] ectoparasites]]

Directly transmitted parasites, not requiring a vector to reach their hosts, include such parasites of terrestrial vertebrates as lice and mites; marine parasites such as [[copepod]]s and [[Cyamidae|cyamid]] amphipods; [[monogenea]]ns; and many species of nematodes, fungi, protozoans, bacteria, and viruses. Whether endoparasites or ectoparasites, each has a single host-species. Within that species, most individuals are free or almost free of parasites, while a minority carry a large number of parasites; this is known as an [[aggregated distribution]].<ref name=PoulinRandhawa2015/>

{{anchor|Autoinfection}}