infestation

pathology

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June 17, 2026

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The term "infestation" refers to the presence of organisms, such as worms or arthropods, on or in a host. This presence is not necessarily parasitic. Infestations can cause significant economic damage, as seen with sheep-strike caused by blowflies.12

Insects can also be vectors for diseases, transmitting pathogens that cause illnesses like malaria, transmitted by mosquitoes, or plague, spread by fleas. Parasitic diseases are caused by organisms like protozoans and helminths (worms). For example, Ascaris lumbricoides causes ascariasis, a widespread infection where the worms live in the human intestine. Other parasitic infections include those caused by whipworms and pinworms, which can lead to various gastrointestinal issues.234

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animal disease
Infectious and noninfectious diseases
The term infestation indicates that animals, including spiny-headed worms (Acanthocephala), roundworms (Nematoda), flatworms (Platyhelminthes), and arthropods such as lice, fleas, mites, and ticks, are present in or on the body of a host. An infestation is not necessarily parasitic.
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The term infestation indicates that animals, including spiny-headed worms (Acanthocephala), roundworms (Nematoda), flatworms (Platyhelminthes), and arthropods such as lice, fleas, mites, and ticks, are present in or on the body of a host. An infestation is not necessarily parasitic.
Read More