Trematoda is a class of flatworms known as flukes or trematodes. They are obligate internal parasites with a complex life cycle requiring at least two hosts. The intermediate host, in which asexual reproduction occurs, is usually a snail. The definitive host, where the flukes sexually reproduce, is a vertebrate. Infection by trematodes can cause disease in all five traditional vertebrate classes: mammals, birds, amphibians, reptiles, and fish.
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.
Digenea is a class of trematodes in the Platyhelminthes phylum, consisting of parasitic flatworms with a syncytial tegument and, usually, two suckers, one ventral and one oral. Adults commonly live within the digestive tract, but occur throughout the organ systems of all classes of vertebrates. Once thought to be related to the Monogenea, it is now recognised that they are closest to the Aspidogastrea and that the Monogenea are more closely allied with the Cestoda. Around 6,000 species have been described to date.
Fasciolopsiasis results from an infection by the trematode Fasciolopsis buski, the largest intestinal fluke of humans, growing up to 7.5 cm (3.0 in) long.
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.
Liver fluke is a collective name of a polyphyletic group of parasitic trematodes under the phylum Platyhelminthes. They are principally parasites of the liver of various mammals, including humans. Capable of moving along the blood circulation, they can occur also in bile ducts, gallbladder, and liver parenchyma. In these organs, they produce pathological lesions leading to parasitic diseases. They have complex life cycles requiring two or three different hosts, with free-living larval stages in water.
Schistosoma nasale is a species of digenetic trematode in the family Schistosomatidae. S. nasale inhabits blood vessels of the nasal mucosa and causes "snoring disease" in cattle, but remains symptomless in buffaloes though extruding its eggs in nasal discharge. The first intermediate host is a freshwater snail Indoplanorbis exustus that may be the sole natural intermediate host for Schistosoma nasale on the Indian sub-continent.
Schistosoma indicum is a species of digenetic trematode in the family Schistosomatidae. The parasite is widespread in domestic animals in India and other Asian countries.
Griphobilharzia amoena is a significant trematode that infect crocodiles such as the Australian freshwater crocodile, Crocodylus johnstoni, located in Darwin, Australia with reported illness in Irian Jaya as well. They possess a distinctive tegument that is composed of two lipid bilayers instead of a single bilayer. The double bilayer may be an adaptation to survive the host's immune response.
Biomphalaria glabrata is a species of air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails.
Artyfechinostomum malayanum is a species of digenetic trematode in the family Echinostomatidae.
Hypoderaeum conoideum is a species of digenetic trematodes in the family Echinostomatidae.
Clinostomum marginatum is a species of parasitic fluke. It is commonly called the "yellow grub". It is found in many freshwater fish in North America, and no fish so far is immune to this parasite. It is also found in frogs. Clinostomum marginatum can also be found in the mouth of aquatic birds such as herons and egrets. They are commonly present in the esophagus of fish-eating birds and reptiles. Eggs of these trematodes are shed in the feces of aquatic birds and released into water. Aquatic birds become hosts of this parasite by ingesting infected freshwater fish. The metacercariae are found right beneath the skin or in the muscles of host fish.
Philophthalmus gralli, commonly known as the Oriental avian eye fluke, parasitises the conjunctival sac of the eyes of many species of birds, including birds of the orders Galliformes and Anseriformes. In Brazil this parasite was reported in native Anseriformes species. It was first discovered by Mathis and Leger in 1910 in domestic chickens from Hanoi, Vietnam. Birds are definitive hosts and freshwater snail species are intermediate hosts. Human cases of philophthalmosis are rare, but have been previously reported in Europe, Asia, and America.
Baracktrema obamai is a species of blood fluke, found in Malaysian freshwater turtles. The discovery prompted the creation of a new genus, Baracktrema. It was discovered in 2015 by a team of American parasitologists led by Thomas R. Platt, and named after U.S. President Barack Obama.
Diplostomum pseudospathaceum is a species of trematode in the family Diplostomidae.
Delane C. Kritsky is an American parasitologist who specialised on the Monogenea, a class of parasitic flatworms which are important ectoparasites of fishes. His research was mainly in the fields of taxonomy, faunistics, and phylogeny of the Monogenea.
Kritsky is a genus of digeneans in the family Aporocotylidae or blood flukes. The name of the genus honours the American parasitologist Delane C. Kritsky.
Aporocotylidae is a family of trematodes within the order Diplostomida, which contains species commonly known as fish blood flukes. It contains more than 40 genera, the largest being Cardicola. Species in this family parasite fish in both fresh and marine water.
Gastropod-borne parasitic diseases (GPDs) are a group of infectious diseases that require a gastropod species to serve as an intermediate host for a parasitic organism that can infect humans upon ingesting the parasite or coming into contact with contaminated water sources. These diseases can cause a range of symptoms, from mild discomfort to severe, life-threatening conditions, with them being prevalent in many parts of the world, particularly in developing regions. Preventive measures such as proper sanitation and hygiene practices, avoiding contact with infected gastropods and cooking or boiling food properly can help to reduce the risk of these diseases.
