Schistosoma is a genus of trematodes, commonly known as blood flukes. They are parasitic flatworms responsible for a highly significant group of infections in humans termed schistosomiasis, which is considered by the World Health Organization as the second-most socioeconomically devastating parasitic disease, with hundreds of millions infected worldwide.
Schistosoma mansoni is a water-borne parasite of humans, and belongs to the group of blood flukes (Schistosoma). The adult lives in the blood vessels near the human intestine. It causes intestinal schistosomiasis. Clinical symptoms are caused by the eggs. As the leading cause of schistosomiasis in the world, it is the most prevalent parasite in humans. It is classified as a neglected tropical disease. As of 2021, the World Health Organization reports that 251.4 million people have schistosomiasis and most of it is due to S. mansoni. It is found in Africa, the Middle East, the Caribbean, Brazil, Venezuela and Suriname.
Schistosoma intercalatum is a parasitic worm found in parts of western and central Africa. There are two strains: the Lower Guinea strain and the Zaire strain. S. intercalatum is one of the major agents of the rectal form of schistosomiasis, also called bilharzia. It is a trematode, and being part of the genus Schistosoma, it is commonly referred to as a blood-fluke since the adult resides in blood vessels.
Schistosoma haematobium is a species of digenetic trematode, belonging to a group (genus) of blood flukes (Schistosoma). It is found in Africa and the Middle East. It is the major agent of schistosomiasis, the most prevalent parasitic infection in humans. It is the only blood fluke that infects the urinary tract, causing urinary schistosomiasis, and is the leading cause of bladder cancer. The diseases are caused by the eggs.
Bulinus is a genus of small tropical freshwater snails, aquatic gastropod mollusks in the family Bulinidae, the ramshorn snails and their allies.
Bulinus nyassanus is a species of small air-breathing freshwater snail with a sinistral shell, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ramshorn snails and their allies. This species is endemic to Lake Malawi in Africa, where found both in shallow and relatively deep water. Its shell generally reached a size of up to around 14 mm × 11 mm.
Bulinus truncatus is a species of air-breathing freshwater snail with a sinistral shell, an aquatic pulmonate gastropod mollusk in the subfamily Bulininae of the family Bulinidae, the ram's horn snails and the like.
Freshwater snails are gastropod mollusks that live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs to major rivers. The great majority of freshwater gastropods have a shell, with very few exceptions. Some groups of snails that live in freshwater respire using gills, whereas other groups need to reach the surface to breathe air. In addition, some are amphibious and have both gills and a lung. Most feed on algae, but many are detritivores and some are filter feeders.
Indoplanorbis is a genus of air-breathing freshwater snail. Its only member species is Indoplanorbis exustus, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails. The species is widely distributed across the tropics. It serves as an important intermediate host for several trematode parasites. The invasive nature and ecological tolerance of Indoplanorbis exustus add to its importance in veterinary and medical science.
Bulinus forskalii is a species of tropical freshwater snail with a sinistral shell, an aquatic gastropod mollusk in the family Bulinidae, the ramshorn snails and their allies.
Bulinus globosus is a species of a tropical freshwater snail with a sinistral shell, an aquatic gastropod mollusk in the family Planorbidae, the ramshorn snails and their allies.
Bulinus abyssinicus is a species of tropical freshwater snail with a sinistral shell, an aquatic gastropod mollusk in the family Planorbidae, the ramshorn snails and their allies.
Bulinus jousseaumei is a species of tropical freshwater snail, an aquatic gastropod mollusk in the family Planorbidae, the ramshorn snails and their allies. Like other planorbids, the shell of the species is sinistral in coiling.
Bulinus nasutus is a species of tropical freshwater snail with a sinistral shell, an aquatic gastropod mollusk in the family Planorbidae, the ramshorn snails and their allies.
The Cavu or rivière de Cavu, is a short river in the Corse-du-Sud department of Corsica which discharges into the Tyrrhenian Sea, and the Mediterranean Sea. In 2014 the Cavu became the first place of re-emerging schistosomiasis in Europe. As of 2016 120 people have become infected after bathing in it.
Schistosoma bovis is a two-host blood fluke, that causes intestinal schistosomiasis in ruminants in North Africa, Mediterranean Europe and the Middle East. S. bovis is mostly transmitted by Bulinus freshwater snail species. It is one of nine haematobium group species and exists in the same geographical areas as Schistosoma haematobium, with which it can hybridise. S. bovis-haematobium hybrids can infect humans, and have been reported in Senegal since 2009, and a 2013 outbreak in Corsica.
Carcinogenic parasites are parasitic organisms that depend on other organisms for their survival, and cause cancer in such hosts. Three species of flukes (trematodes) are medically-proven carcinogenic parasites, namely the urinary blood fluke, the Southeast Asian liver fluke and the Chinese liver fluke. S. haematobium is prevalent in Africa and the Middle East, and is the leading cause of bladder cancer. O. viverrini and C. sinensis are both found in eastern and southeastern Asia, and are responsible for cholangiocarcinoma. The International Agency for Research on Cancer declared them in 2009 as a Group 1 biological carcinogens in humans.
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