A genus of trematodes, Schistosoma spp., commonly known as blood-flukes and bilharzia, cause the most important human helminth infection (schistosomiasis) from a world health perspective, and are considered by the World Health Organization as second in importance only to malaria, with hundreds of millions infected worldwide. Adult worms parasitize mesenteric blood vessels. Eggs are passed through urine or feces to fresh water, where larval stages can infect a new host by penetrating the skin. Orders not necessarily a complete list Azygiida Echinostomida Opisthorchiida Plagiorchiida Strigeata Strigeatida Trematodes are also known as flukes. ... Classes Monogenea Trematoda Cestoda Turbellaria The flatworms (Platyhelminthes, Greek platy: flat; helminth: worm) are a phylum of relatively simple soft-bodied invertebrate animals. ... Skin vesicles created by the penetration of Schistosoma. ... WHO emblem The World Health Organization (WHO) is an agency of the United Nations, acting as a coordinating authority on international public health, headquartered in Geneva, Switzerland. ... Red blood cell infected with Malaria (Italian: bad air; formerly called ague or marsh fever in English) is an infectious disease which in humans causes about 350-500 million infections and approximately 1. ... The circulatory system or cardiovascular system is the organ system which circulates blood around the body of most animals. ... Urine is liquid waste excreted by the kidneys and is produced by the process of filtration. ... Rabbit feces are usually 8-10 mm in diameter and dry to the touch. ... For the village on the Isle of Wight, see Freshwater, Isle of Wight. ...

? Schistosoma
Schistsoma mansoni egg
Scientific classification
Kingdom: Animalia Phylum: Platyhelminthes Class: Trematoda Subclass: Digenea Order: Strigeiformes Family: Schistosomatidae Genus: Schistosoma Weinland, 1858
Species within the genus Schistosoma
S. mansoni S. japonicum S. mekongi S. intercalatum S. haematobium S. indicum S. nasale S. leiperi S. malayensis S. rodhaini Schistosoma mansoni File links The following pages link to this file: Schistosoma Categories: Department of Health and Human Services images ... Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. ... Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria (coral, jellyfish, anenomes) Placozoa (trichoplax) Subregnum Bilateria (bilateral symmetry) Acoelomorpha (basal) Orthonectida (flatworms, echinoderms, etc. ... Classes Monogenea Trematoda Cestoda Turbellaria The flatworms (Platyhelminthes, Greek platy: flat; helminth: worm) are a phylum of relatively simple soft-bodied invertebrate animals. ... Subclasses Aspidogastrea Digenea The Trematoda is a class within the phylum Platyhelminthes, which contains two groups of parasitic worms. ... Orders within the Digenea Strigeidida Azygiida Echinostomida Plagiorchiida Opisthorchiida The digenea (Gr. ... Schistosomatidae is a family of digenetic trematodes with complex parasitic life cycles. ... Binomial name Schistosoma mansoni Sambon, 1907 Schistosoma mansoni is an important human parasite. ... Binomial name Schistosoma japonicum (Katsurada, 1904) Schistosoma japonicum is an important parasite. ... Binomial name Schistosoma mekongi Voge, Bruckner & Bruce, 1978 Schistosoma mekongi is an important parasite. ... Binomial name Schistosoma intercalatum Fisher, 1934 Schistosoma intercalatum is an important parasite. ... Binomial name Schistosoma haematobium (Bilharz, 1852) Schistosoma haematobium is an important parasite. ... Binomial name Schistosoma malayensis Greer, Ow-Yang & Yong, 1988 Schistosoma malayensis is an important parasite. ...

Taxonomy

There are four species of schistosome which are infective to humans:

• Schistosoma mansoni, found in Africa, Brazil, Venezuela, Suriname, the lesser Antilles, Puerto Rico, and the Dominican Republic. It is also known as Manson's blood fluke or swamp fever. Freshwater snails of the Biomphalaria genus are an important host for this trematode.

• S. japonicum whose common name is simply blood fluke is found widely spread in Eastern Asia and the southwestern Pacific region. In Taiwan this species only affects animals, not humans. Freshwater snails of the Oncomelania genus are an important host for S. japonicum.

• S. mekongi is related to S. japonicum and affects both superior and inferior mesenteric veins. S. mekongi differs in that it has smaller eggs, a different intermediate host, and longer prepatent period in the mammalian host.

• S. haematobium, commonly referred to as the bladder fluke, originally found in Africa, the Near East, and the Mediterranean basin, was introduced into India during World War II. Freshwater snails of the Bulinus genus are an important host for this parasite.

S. indicum, S. nasale, S. leiperi are all parasites of ruminants. Binomial name Schistosoma mansoni Sambon, 1907 Schistosoma mansoni is an important human parasite. ... // Etymology World map showing Africa (geographically) The name Africa came into Western use through the Romans, who used the name Africa terra — land of the Afri (plural, or Afer singular) — for the northern part of the continent, as the province of Africa with its capital Carthage, corresponding to modern-day... The Antilles now generally refers to the islands of the Caribbean or West Indies, except the Bahamas. ... Species Species Biomphalaria glabrata Species Biomphalaria obstructa Species Biomphalaria amazonica Species Biomphalaria pfeifferi Species Biomphalaria tenagophila Species Biomphalaria havanensis Species Biomphalaria straminea Species Biomphalaria alexandrina Species Biomphalaria subprona Biomphalaria is an important genus of snail that serves as a natural host for the schistomasomiasis blood fluke. ... Binomial name Schistosoma japonicum (Katsurada, 1904) Schistosoma japonicum is an important parasite. ... East Asia is a subregion of Asia. ... For other meanings of Pacific, see Pacific (disambiguation). ... Genera Genus Oncomelania Oncomelania is a genus of snail. ... Binomial name Schistosoma mekongi Voge, Bruckner & Bruce, 1978 Schistosoma mekongi is an important parasite. ... Binomial name Schistosoma haematobium (Bilharz, 1852) Schistosoma haematobium is an important parasite. ... The Near East is a term commonly used by archaeologists and historians, less commonly by journalists and commentators, to refer to the region encompassing the Levant (modern Israel, Jordan, Syria and Lebanon), Anatolia (modern Turkey), Mesopotamia (Iraq and eastern Syria), and the Iranian Plateau (Iran). ... The Mediterranean Sea is an intercontinental sea positioned between Europe to the north, Africa to the south and Asia to the east, covering an approximate area of 2. ... [[{{{diversity_link}}}|Diversity]] {{{diversity}}} Binomial name {{{binomial}}} Trinomial name {{{trinomial}}} Type Species {{{type_species}}} {{{subdivision_ranks}}} [[Image:{{{range_map}}}|{{{range_map_width}}}|]] Synonyms {{{synonyms}}} Bulinus is an important genus of fresh-water snail. ... A ruminant is any hooved animal that digests its food in two steps, first by eating the raw material and regurgitating a semi-digested form known as cud, then eating the cud, a process called ruminating. ...

Morphology

Adult schistosomes share all the fundamental features of the digenea. They have a basic bilateral symmetry, oral and ventral suckers, a body covering of a syncytial tegument, a blind-ending digestive system consisting of mouth, oesophagus and bifurcated caeca; the area between the tegument and alimentary canal filled with a loose network of mesoderm cells, and an excretory or osmoregulatory system based on flame cells. Adult worms tend to be 10-20 mm long and use globins from their hosts' hemoglobin for their own circulatory system. The elaborate patterns on the wings of butterflies are one example of biological symmetry . ... In biology, a syncytium is a large region of cytoplasm that contains many nuclei. ... In zootomy, the integumentary system is often the largest organ system of an animal, comprising skin, hair, feathers, scales, nails, skin glands and their products (sweat, slime). ... For the Physics term GUT, please refer to Grand unification theory The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and... Sagittal section of nose mouth, pharynx, and larynx. ... The esophagus, oe/œsophagus*, or gullet is the muscular tube in vertebrates through which ingested food passes from the mouth area to the stomach. ... In anatomy of the digestive system, the cecum or caecum is a pouch connected to the large intestine between the ileum. ... It has been suggested that endoderm be merged into this article or section. ... Cells in culture, stained for keratin (red) and DNA (green) The cell is the structural and functional unit of all living organisms, and are sometimes called the building blocks of life. ... A flame cell is a specialized excretory cell found in the Platyhelminthes (except the tubellarian order Acoela), these are the simplest animals to have a dedicated excretory system. ... A globular protein is a protein that is globe-like, or rounded in shape, often soluble in aqueous solution. ... 3-dimensional structure of hemoglobin. ...

Reproduction

Unlike other trematodes, the schistosomes are dioecious - i.e., the sexes are separate. The two sexes display a strong degree of sexual dimorphism, and the male is considerably larger than the female. The male surrounds the female and encloses her within his gynacophoric canal for the entire adult lives of the worms, where they reproduce sexually. In biology, Dioecious is an adjective which indicates the exisistence of separate sexes in a species of organisms. ... Female (left) and male Common Pheasant, illustrating the dramatic difference in form between the sexes Sexual dimorphism is the systematic difference in form between individuals of different sex in the same species. ...

See also

For a full discussion of life cycles, symptoms and control measures, see the main article on schistosomiasis. A life cycle includes the major sexual stages of a species, especially in regard to its ploidy. ... The term symptom (from the Greek syn = con/plus and pipto = fall, together meaning co-exist) has two similar meanings in the context of physical and mental health: A symptom may loosely be said to be a physical condition which shows that one has a particular illness or disorder (see... Skin vesicles created by the penetration of Schistosoma. ...

External links

• British Department for International Development Control of Schistosomiasis
• The World Health Organisation
• University of Cambridge Schistosome Laboratory