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Parasite Definitions
Intestinal Roundworms
(Ascaris Lumbricoides and Ascaris Suum)
Ascaris are parasitic worms in the intestines of various terrestrial animals, chiefly herbivores. They are typically large worms characterized by a mouth surrounded by three lips. The species Ascaris lumbricoides is probably the most familiar parasite in humans. An almost identical worm, often called A. suum, occurs in pigs. The intestinal roundworm Ascaris lumbricoides infection in humans follows the ingestion of Ascaris eggs that have contaminated foods or soil. In the small intestine the larvae are liberated and migrate through the intestinal wall, reaching the lungs, where they may produce a host sensitization that results in lung inflammation and fluid retention. About 10 days later, the larvae pass from the respiratory passages into the digestive tract and mature into egg-producing worms, which grow to some 15 to 40 cm (6 to 16 inches) in length, in the small intestine. Serious, even fatal, complications of ascariasis result from the infiltration of the larvae into sensitive tissues, such as the brain, and from the migration of the adult worms into various body structures where they produce abcesses and toxic manifestations. Ascariasis exists worldwide and is believed to affect some 660 million persons.
Pinworms
(Enterobius vermicularis, Oxyuris spp.)
Pinworms are common human intestinal parasites, especially in children. They are also found in other vertebrates. Male pinworms are 2 to 5 mm (about 0.08 to 0.2 inch) long; females range in length from 8 to 13 mm. The long tails of the worms give them a pinlike appearance. Pinworms usually occur in the large intestine but sometimes are found in the small intestine, the stomach, or farther up the gastrointestinal tract. After the eggs are fertilized by the male, the female travels to the anus, deposits the eggs on the skin near the anal opening, and usually dies. Movements of the worm on the skin cause itching. Eggs, transferred beneath the fingernails by scratching, are passed to the mouth, from which the eggs or larvae make their way to the intestine. The life cycle requires 15 to 43 days.
Eggs on contaminated fingers re-enter via the mouth, but remain viable for several days on surfaces around the house. Often, an entire family is infected. Many doctors believe at at least 10% of the U.S. population harbors pinworms.
Tapeworms
(Hymenolepis Nana)
Hymenolepis Nana (Tapeworm), is one of a group of flattened and tapelike hermaphroditic worms that are intestinal parasites in humans and other animals, producing larvae that can invade body tissues.
For humans there are two kinds of tapeworm infestations: (1) intestinal cestodiasis, in which the mature worm lives in the intestine, producing eggs that are evacuated in the feces and develop further in other animal hosts, and (2) visceral and somatic cestodiasis, in which the larvae form lesions in body organs. Thirty or more species of tapeworms cause intestinal cestodiasis in humans. The more common ones include the following: Taenia saginata, or beef tapeworm, about 4.5 to 6 m (15 to 20 feet) long; Taenia solium, or pork tapeworm, about 2 to 3 m long; and Diphyllobothrium latum, about 9 m long, acquired by the eating of undercooked beef, pork, or fish that harbour larval forms of the worms. Hymenolepis nana, or dwarf tapeworm, only a few centimetres long, releases eggs that require no intermediate hosts. It is possibly the most common cestode found in humans, affecting chiefly children. Symptoms of intestinal cestodiasis include abdominal pain that may be relieved by eating and that may be associated with distention, flatulence, and nausea. Often, however, there are no symptoms, and first notice of infestation may occur only when segments of the worms are passed in the stools.
Hookworms
(Ancylostoma spp. and Necator spp.)
Hookworm infection begins when the worm is in the larval stage. It penetrates the skin and migrates during its life cycle through the liver and the lungs, and it attaches to the mucosa of the small intestine where it matures. Hookworms deplete the body of nutrients, and a major effect is severe chronic iron-deficiency anemia. Necator americanus, which ranges in size from 5 to 11 millimetres (0.2 to 0.4 inch), is responsible for about 90 percent of human hookworm infections that occur in tropical and subtropical regions of the world. Ancylostoma duodenale, 8 to 13 millimetres long, is found on all continents but is most prevalent in warm regions. A. braziliense, from 8 to 11 millimetres long, is normally parasitic in dogs and cats; man, however, is sometimes infected by this species in the southern United States, South America, and Asia. A. ceylanicum, normally parasitic in dogs, is sometimes found in man in South America and Asia. A. duodenale, possesses four hooklike teeth in its adult stage, and N. americanus has plates in its mouth rather than teeth.
Both species of hookworm have similar life cycles. The adult worm attaches itself to the mucosal tissue lining the small intestine, where the female may produce several thousands eggs a day, which are passed in the feces. If the fecal matter reaches suitable soil, the eggs are hatched, and the infective, threadlike larvae may penetrate human skin, usually that of the foot, by way of the sweat glands and hair follicles. They then invade the lymph and blood vessels, reach the lungs, and pass up the respiratory tree to reach the mouth, where they are swallowed and sent to the small intestine; there they mature and start a new reproductive cycle. The intestinal parasites are reputedly long-lived, with a lifetime that may span some 10 years.
The symptoms of hookworm disease ordinarily begin with ground itch, an itchy skin irritation caused by the larvae when they penetrate the skin and marked by papules and vesicles that are often located between the toes. In passing through the lungs, the larvae may produce coughing and fever. In the intestine, the mature worm sustains its life by bloodsucking, and persistent feeding by many worms over many years results in secondary anemia.
In heavy infestations (which may involve more than 500 larvae), the general symptoms include pallor of the skin and mucous membranes, fluid retention in the face and extremities, constipation alternating with diarrhea, abdominal tenderness, increased appetite for bulky or strange substances (e.g., clay), delayed puberty and stunted growth, fatigue, dullness, and apathy. Hookworm infestation tends to be constantly widespread in varied regions of the world.
Intestinal Fluke
(Fasciolopsis Buski )
The adult worms, 2-7.5 cm (0.8-3 inches) long, attach themselves to the tissues of the small intestine of the host by means of ventral suckers; the sites of attachment may later ulcerate and form abscesses. In the early stage of the infection, there is usually abdominal pain, as well as diarrhea and nausea alternating with constipation. Heavy infestations that go untreated cause general body weakness and fluid retention, which may have serious consequences, especially in children.
Chronic infections with this parasite lead to inflammation, ulceration, hemorrhage, and abscesses of the small intestine, and these can ultimately lead to the host's death. Dr. Hulda Clark has done extensive, conclusive research on the effects of the Fluke Parasite in relation to many of the diseases and illnesses that plague humans. Dr. Clark considers this parasite, once it has migrated out of the intestinal tract and into other areas of the body, to be one of the most destructive and dangerous invader to the human body. Fluke infestation symptoms may include urinary problems, liver problems, hepatitis, abdominal pain, liver abscesses, fibrosis, diarrhea, vomiting, and an-ever increasing belief in it's direct relationship to cancer and aids
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