Ascaris lumbricoides

Ascaris lumbricoides Intestinal Roundworm	Contents	Rev 09/23/2022
	Classification	Biology and Ecology
	Morphology and Anatomy	Life Cycle
Return to Ascaris menu		Ecosystem Functions and Services
	Distribution	Management
Return to Ascarididae Menu	Feeding	References
	Go to Nemaplex Main Menu	Go to Dictionary of Terminology

Classification

Class: Chromadorea; SubClass: Chromadoria; Order: Rhabditida; Superfamily: Ascaridoidea; Family: Ascarididae

Morphology and Anatomy:


A tangled mass of Ascaris worms

Reported median body size for this species (Length mm; width micrometers; weight micrograms) - Click:

Distribution

Economic Importance:

Hosts:

Feeding

Intestinal roundworm

Life Cycle

Adult hookworms (Ancylostoma duodenale and Necator americanus) parasitize the upper part of the human small intestine, whereas Ascaris lumbricoides parasitize the entire small intestine and adult Trichuris trichiura live in the large intestine, especially the caecum.

The parasites can live for several years in the human gastrointestinal tract. After mating, each adult female produces thousands of eggs per day which leave the body in the feces.

Ecophysiological Parameters:

For Ecophysiological Parameters for this species, click	If species level data are not available, click for genus level parameters

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Damage:

Contact with soil contaminated with eggs or larvae of nematode parasites is a common form of transmission that results in human infection. The nematodes can live for years as adults in the human intestinal tract. Soil becomes contaminated by fecal material of infected humans and other animal hosts.

More than a billion people are infected with at least one species. The most important nematode infections of the human gastrointestinal tract are the intestinal roundworm (Ascaris lumbricoides), whipworm (Trichuris trichiura), and hookworm (Necator americanus or Ancylostoma duodenale).

It is common for a single individual, especially a child living in a less developed country, to be chronically infected with all three of the nematode parasites, which results in malnutrition, stunted growth stunting, retarded intellectual development, and cognitive and educational deficiencies.

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Management:

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References:

Bethony, J., Brooker, S., Albonico, M., Geiger, S.M., Loukas, A., Diemert, D., Hotez, P.J. 2006. Soil-transmitted helminth infections: ascariasis, trichuriasis, and hookworm. The Lancet 9521:1521-1532.