| Infestation | |
|---|---|
 | |
| Tick-infested cow | |
| Specialty | Infectious disease |
Infestation is the state of being invaded or overrun bypests orparasites.[1] It can also refer to the actual organisms living on or within ahost.[2]
In general, the term "infestation" refers toparasitic diseases caused byanimals such asarthropods (i.e.mites,ticks, andlice) andworms, but excluding (except) conditions caused byprotozoa,fungi,bacteria, andviruses,[3] which are calledinfections.
Infestations can be classified as either external or internal with regards to the parasites' location in relation to the host.
External orectoparasitic infestation is a condition in which organisms live primarily on the surface of the host (thoughporocephaliasis can penetrate viscerally) and includes those involvingmites,ticks,head lice andbed bugs.[4]
An internal (orendoparasitic) infestation is a condition in which organisms live within the host and includes those involving worms (thoughswimmer's itch stays near the surface).
Sometimes, the term "infestation" is reserved for external ectoparasitic infestations[5] while the terminfection refers to internal endoparasitic conditions.[6]