Echinococcus vogeli | |
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Echinococcus vogeli protoscolex | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Platyhelminthes |
Class: | Cestoda |
Order: | Cyclophyllidea |
Family: | Taeniidae |
Genus: | Echinococcus |
Species: | E. vogeli |
Binomial name | |
Echinococcus vogeli Rausch & Bernstein, 1972 | |
Echinococcus vogeli is a small cyclophyllid tapeworm found in Central and South America. [1] E. vogeli, as well as other members of the genus Echinococcus (especially Echinococcus multilocularis ), produce a disease called echinococcosis. Echinococcosis, also known has hydatidosis, is a result of ingesting the eggs of the genus Echinococcus. E. vogeli is similar to E. multilocularis in that both species produces many small cysts that spread throughout the internal organs of the infected animal. The ingestion of E. vogeli eggs, and the spreading of the cysts through infected host, will result in polycystic echinococcosis.
This parasite has a life cycle involving two mammalian hosts. Bush dogs (Speothos venaticus) and domestic dogs (Canis familiaris) are the definitive hosts, harbouring the adult stage of E. vogeli. The ingestion of a rodent intermediate host containing the hydatid cysts of the tapeworm by a bush or domestic dog often results in a heavy infestation of these tapeworms.
Human polycystic echinococcosis is the rarest type of echinococcosis and is characterized by infiltrative, multi-compartment cysts. [2] Symptoms depend on the location of the cysts. For example, cysts located in a patient's lungs will result in shortness of breath, coughing, and/or chest pain. But, if the cysts reside in the patient's liver, symptoms will include jaundice, abnormal abdominal tenderness, abdominal pain, fever, and/or anaphylactic shock.
The life cycle of E. vogeli utilizes a definitive host and intermediate host, also known as primary and secondary host, respectively, each housing different stages of the parasite. Bush dogs and domestic dogs serve as the definitive host for the adult stage of E. vogeli. Researchers believe that domestic dogs have a role in infecting humans with this tapeworm. [2] The tapeworm attaches itself to the wall of the dogs small intestine via a rostellum armed with hooks. Once the tapeworm matures, eggs are released into the intestine and passed in feces. [3] Rodents, such as the paca, serve as the intermediate host. Eggs that are eaten by the rodent form hydatid cysts in the lungs, liver, and other internal organs. When a bush or domestic dog consumes an infected rodent, the life cycle is complete. Larvae from the cysts of the infected rodent mature inside the small intestine of the dog. [4] Humans are at risk of becoming infected when eating under cooked meat containing hydatid cysts or coming into contact with infected dog feces. But, humans are not the regular hosts of E. vogeli, meaning that humans are the dead-end host; which does not allow transmission to the definitive host.
Echinococcus vogeli has the largest strobila within the Echinococcus genus, reaching a length of 12 mm. [4] This tapeworm resides in the small intestine of bush and domestic dogs. E. vogeli contains a scolex, where a hook-filled rostellum is located, and a long neck that attaches to up to six proglottids. The gravid proglottid, the sexually mature proglottid that releases eggs into the dogs feces, is cylindrical and takes up about half of the strobilar length. [4]
The diagnosis of polycystic echinococcosis involves isolating the protoscoleces during surgery or after the patient's death in order to identify E. vogeli. Imaging, such as ultrasound and CT scans, can also be used to identify polystytic structures, but this method is not preferred as images are similar to other types of echinococcosis and liver cancer. New studies show that PCR may identify E. vogeli in the patient's tissues. [5]
Polycystic echinococcosis (PE) is an extremely lethal helminthic disease in humans, which is caused by the larval form of E. vogeli. Type I PE consists of polycystic masses in the liver and abdominal cavity. Type II also has polcystic masses in the liver and abdominal cavity, but includes hepatic insufficiency. Type III has polcystic masses in the liver and chest cavity. In type IV polycystic masses occur only in the mesenteries. Type V has calcified cysts in the liver and lung. [4] Type II seems to have the highest mortality rate due to the complications involved with hepatic insufficiency. Due to the similarities between liver cancer and polycystic echinococcosis, PE is hard to diagnose and could deadly when metastasized to other organs.
If patients do not undergo treatment, 94% of them will die within 20 years of diagnosis. [6] PE is treated the same as cystic echinococcosis, with mebendazole and albendazole showing definite progress in treating PE. [7] Surgery remains the top treatment against PE. There are less invasive surgical methods partnered with chemotherapy in development.
The parasite E. vogeli resides in neotropical areas, such as Central and South America. Polycystic echinococcosis has infected people in Panama, Colombia, Ecuador, Venezuela, Peru, Brazil, and Suriname. [4] E. vogeli infections seem to be on the rise, with 100 new cases over the past 10 years. [4]
Echinococcosis is a parasitic disease caused by tapeworms of the Echinococcus type. The two main types of the disease are cystic echinococcosis and alveolar echinococcosis. Less common forms include polycystic echinococcosis and unicystic echinococcosis.
Diphyllobothrium is a genus of tapeworms which can cause diphyllobothriasis in humans through consumption of raw or undercooked fish. The principal species causing diphyllobothriasis is D. latum, known as the broad or fish tapeworm, or broad fish tapeworm. D. latum is a pseudophyllid cestode that infects fish and mammals. D. latum is native to Scandinavia, western Russia, and the Baltics, though it is now also present in North America, especially the Pacific Northwest. In Far East Russia, D. klebanovskii, having Pacific salmon as its second intermediate host, was identified.
Hymenolepiasis is infestation by one of two species of tapeworm: Hymenolepis nana or H. diminuta. Alternative names are dwarf tapeworm infection and rat tapeworm infection. The disease is a type of helminthiasis which is classified as a neglected tropical disease.
Alveolar hydatid disease (AHD) is a form of echinococcosis, or a disease that originates from a parasitic flatworm. AHD is caused by an infection of the flatworm species Echinococcus multilocularis. Although alveolar echinococcosis is rarely diagnosed in humans and is not as widespread as cystic echinococcosis, it is also still a serious disease that has a significantly high fatality rate. It is considered one of the most life-threatening helminthic infections humans can have.
Taenia solium, the pork tapeworm, belongs to the cyclophyllid cestode family Taeniidae. It is found throughout the world and is most common in countries where pork is eaten. It is a tapeworm that uses humans as its definitive host and pigs as the intermediate or secondary hosts. It is transmitted to pigs through human feces that contain the parasite eggs and contaminate their fodder. Pigs ingest the eggs, which develop into larvae, then into oncospheres, and ultimately into infective tapeworm cysts, called cysticercus. Humans acquire the cysts through consumption of uncooked or under-cooked pork and the cysts grow into adult worms in the small intestine.
Taenia is the type genus of the Taeniidae family of tapeworms. It includes some important parasites of livestock. Members of the genus are responsible for taeniasis and cysticercosis in humans, which are types of helminthiasis belonging to the group of neglected tropical diseases. More than 100 species are recorded. They are morphologically characterized by a ribbon-like body composed of a series of segments called proglottids; hence the name Taenia. The anterior end of the body is the scolex. Some members of the genus Taenia have an armed scolex ; of the two major human parasites, Taenia saginata has an unarmed scolex, while Taenia solium has an armed scolex.
Echinococcus is a genus within Cestoda, a parasitic class of the platyhelminthes phylum. Human echinococcosis is an infectious disease caused by the following species: E. granulosus, E. multilocularis, E. vogeli or E. oligarthrus.
Echinococcus granulosus, also called the hydatid worm or dog tapeworm, is a cyclophyllid cestode that dwells in the small intestine of canids as an adult, but which has important intermediate hosts such as livestock and humans, where it causes cystic echinococcosis, also known as hydatid disease. The adult tapeworm ranges in length from 3 mm to 6 mm and has three proglottids ("segments") when intact—an immature proglottid, mature proglottid and a gravid proglottid. The average number of eggs per gravid proglottid is 823. Like all cyclophyllideans, E. granulosus has four suckers on its scolex ("head"), and E. granulosus also has a rostellum with hooks. Several strains of E. granulosus have been identified, and all but two are noted to be infective in humans.
Echinococcus multilocularis, the fox tapeworm, is a small cyclophyllid tapeworm found extensively in the northern hemisphere. E. multilocularis, along with other members of the Echinococcus genus, produce diseases known as echinococcosis. Unlike E. granulosus,E. multilocularis produces many small cysts that spread throughout the internal organs of the infected animal. The resultant disease is called alveolar echinococcosis, and is caused by ingesting the eggs of E. multilocularis.
Dipylidium caninum, also called the flea tapeworm, double-pored tapeworm, or cucumber tapeworm is a cyclophyllid cestode that infects organisms afflicted with fleas and canine chewing lice, including dogs, cats, and sometimes human pet-owners, especially children.
Taenia pisiformis, commonly called the rabbit tapeworm, is an endoparasitic tapeworm which causes infection in lagomorphs, rodents, and carnivores. Adult T. pisiformis typically occur within the small intestines of the definitive hosts, the carnivores. Lagomorphs, the intermediate hosts, are infected by fecal contamination of grasses and other food sources by the definitive hosts. The larval stage is often referred to as Cysticercus pisiformis and is found on the livers and peritoneal cavities of the intermediate hosts. T. pisiformis can be found worldwide.
Eucestoda, commonly referred to as tapeworms, is the larger of the two subclasses of flatworms in the class Cestoda. Larvae have six posterior hooks on the scolex (head), in contrast to the ten-hooked Cestodaria. All tapeworms are endoparasites of vertebrates, living in the digestive tract or related ducts. Examples are the pork tapeworm with a human definitive host, and pigs as the secondary host, and Moniezia expansa, the definitive hosts of which are ruminants.
Hans Vogel was a German scientist known for his work in helminthology. For much of his career he was associated with the Bernhard Nocht Institute for Tropical Medicine in Hamburg.
Cestoda is a class of parasitic worms in the flatworm phylum (Platyhelminthes). Most of the species—and the best-known—are those in the subclass Eucestoda; they are ribbon-like worms as adults, known as tapeworms. Their bodies consist of many similar units known as proglottids—essentially packages of eggs which are regularly shed into the environment to infect other organisms. Species of the other subclass, Cestodaria, are mainly fish infecting parasites.
Taenia taeniaeformis is a parasitic tapeworm, with cats as the primary definitive hosts. Sometime dogs can also be the definitive host. The intermediate hosts are rodents and less frequently lagomorphs (rabbits). The definitive host must ingest the liver of the intermediate host in order to acquire infection. The worm tends to be white, thick bodied, and around 15 to 60 cm in length. This species of tape worm is much less frequently encountered than Dipylidium caninum, which has fleas as its intermediate host rather than rodents but exhibits most of the same physical characteristics and is treated with the same medications.
Coenurosis is a parasitic infection that results when humans ingest the eggs of dog tapeworm species Taenia multiceps, T. serialis, T. brauni, or T. glomerata.
Hymenolepis microstoma, also known as the rodent tapeworm, is an intestinal dwelling parasite. Adult worms live in the bile duct and small intestines of mice and rats, and larvae metamorphose in the haemocoel of beetles. It belongs to the genus Hymenolepis; tapeworms that cause hymenolepiasis. H. microstoma is prevalent in rodents worldwide, but rarely infects humans.
Taenia serialis, also known as a Canid tapeworm, is found within canines such as foxes and dogs. Adult T. serialis are parasites of carnivores, particularly dogs, with herbivorous lagomorph mammals such as rabbits and hares, serving as intermediate hosts. In definitive hosts, T. serialis is acquired by eating tissues from a variety of intermediate hosts. Accidental infection of humans though, can occur when eggs are ingested from food or water contaminated with dog feces and the human then becomes the T. serialis intermediate host.
Joyeuxiella pasquale is a species of flatworm, belonging to the family Dipylidiidae. The species uses coprophagous beetles and reptiles as transportation hosts with dogs, cats, and other wild carnivores being their final carrier for reproduction.
Cat worm infections, the infection of cats (Felidae) with parasitic worms, occur frequently. Most worm species occur worldwide in both domestic and other cats, but there are regional, species and lifestyle differences in the frequency of infestation. According to the classification of the corresponding parasites in the zoological system, infections can be divided into those caused by nematode and flatworms - in the case of the latter, mainly cestoda and trematoda - while other strains are of no veterinary significance. While threadworms usually do not require an intermediate host for their reproduction, the development cycle of flatworms always proceeds via alternate hosts.