The Relationship Between Intestinal Parasites and Allergy



Intestinal nematodes are a class of parasites that live in the intestine and are nonsegmented, cylindrical worms with a tough protective covering. These worms sexually reproduce and have complete digestive systems. These parasites have egg, larva, and adult stages, and a diagnosis of intestinal nematodes is usually made based on the presence of eggs in the feces. While many nematodes are free living, and do not require a host, there are several common intestinal parasites found in humans worldwide. The most common intestinal nematodes are Ascaris, Necator and Ancylostomoa (Hookworm), Trichuris (Whipworm), and Strongyloides. These parasites are found around the world, mostly in temperate and tropical zones, and often with greater prevalence in less developed countries. Even though poor sanitation of third world countries may contribute to much higher prevalence of intestinal nematodes than in developed countries, there have been documented cases of these parasites in developed countries like the United States .

For further information on these parasites see:





John, David T., and William A. Petri. Markell and Voge's Medical Parasitology. 9th ed. Saunders, 2006. 240-242.


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