And, unfortunately, it prefers to prey on humans: Tunga penetrans, aka the chigoe flea.
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In a seminal paper on the biology and pathology of Tunga penetrans, Eisele et al. (2003) provided and detailed the five stages of tungiasis, thereby detailing the in vivo development of the female chigoe flea for the first time. In dividing the natural history of the disease, the Fortaleza Classification formally describes the last part of the female flea's life cycle where it burrows into its host's skin, expels eggs, and dies. Stage 1 is characterized by the penetration of the skin by the female chigoe flea.
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The chigoe flea or jigger (Tunga penetrans) causes the disease tungiasis, a major public health problem around the world. Fleas that specialize as parasites on specific mammals may use other mammals as hosts; thus, humans may be bitten by cat and dog fleas.
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Tunga penetrans (chigoe flea or jigger) is a parasitic insect found in most tropical and sub-tropical climates. It is native to Central and South America, and has been inadvertently introduced by humans to sub-Saharan Africa.Cestari TF, Pessato S, Ramos-e-Silva M Tungiasis and myiasis. Clin Dermatol.
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In a seminal paper on the biology and pathology of Tunga penetrans, Eisele et al. (2003) provided and detailed the five stages of tungiasis, thereby detailing the in vivo development of the female chigoe flea for the first time. In dividing the natural history of the disease, the Fortaleza Classification formally describes the last part of the female flea's life cycle where it burrows into its host's skin, expels eggs, and dies. Due to the nature of the discussion, overlap with other sections, particularly the one on symptoms, is unavoidable. Stage 1 is characterized by the penetration of the skin by the female chigoe flea. Running along the body, the female uses its posterior legs to push its body upward by an angle of 45–90 degrees.
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Academy of American Franciscan History, 1959, vol. 1, pp. 86–7. Geiger discussed Serra's wound with three medical doctors—one of them Mexican—to fact-check this account from Serra and his first biographer, Francisco Palóu. Serra's wound may have been caused either by a mosquito bite or infestation by a "chigger," more precisely a chigoe flea.
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Though the chigoe flea resembles most others in morphology, the flea has a hypertrophic region between tergites 2 and 3. As stated in Eisele et al. (2003), tergites 2 and 3, as well as the abdominal sternites, stretch considerably and are bent apart. Chitinous clasps that are built for the abdominal enlargement surround these regions and hold onto the hypertrophic zone, giving them the appearance of a three-leafed clover.
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Eggs will be expelled whether or not they have been fertilized. The chigoe flea eggs’ average length is 604 μm and the just hatched larvae, in their first instar, have an average length of 1,500 μm. At the second and last instar (T. penetrans is unique among the fleas in that it only has two, instead of three, instars.) the larvae decrease in size to 1,150 μm after growing to at least 2,900 μm.
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Nevertheless, due to the high incidence of secondary infection, those at risk of tungiasis should get vaccinated against tetanus. A better approach is to use repellents that specifically target the chigoe flea. One very successful repellent is called Zanzarin, a derivative of coconut oil, jojoba oil, and aloe vera. In a recent study involving two cohorts, the infestation rates dropped 92% on average for the first one and 90% for the other.
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Occurrences of fleas on reptiles is accidental, and fleas have been known to feed on the hemolymph (bloodlike body fluid) of ticks. Flea phylogeny was long neglected, the discovery of homologies with the parts of other insects being made difficult by their extreme specialization. Whiting and colleagues prepared a detailed molecular phylogeny in 2008, with the basic structure shown in the cladogram. The Hectopsyllidae, including the harmful chigoe flea or jigger, is sister to the rest of the Siphonaptera.
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In a study of 1000 freshly ejected T. penetrans eggs, it was found that females are generally smaller than males for all criteria. In some cases, though, females had a bigger epipharynx and maxillar palpus. Due to its burrowing activity, the chigoe flea has developed a well-developed lacinia and epipharynx that is used to penetrate the skin. Overall, the fleas’ head is relatively flattened, which again aids in burrowing through the epidermal and dermal layers.
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Due to the high number of hosts, eradication of tungiasis is not feasible, at least not easily so. Public health and prevention strategies should then be done with elimination as the target. Better household hygiene, including having a cemented rather than a sand floor, and washing it often, would lower the rates of tungiasis significantly. Though vaccines would be useful, due to the ectoparasitic nature of chigoe flea, they are neither a feasible nor an effective tool against tungiasis.
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Trombicula species of mites are sometimes known, when in the larval stage, as berry bug, harvest mites, or chiggers (but not to be confused with jigger or chigoe flea). They feed on blood, but only in the larval stage. The lifecycle starts with eggs laid in the environment of the normal hosts of the larvae, typically rodents and other small mammals. Larvae quest for hosts whilst on vegetation in the same way in which many larval ticks do.
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For the most part, the chigoe flea lives 2–5 cm below the sand, an observation which helps explains its overall distribution. The temperature is generally too hot for the larvae to develop on the surface of the sand and the deeper sand does not have enough oxygen. This preferred ecological niche offers a way to decrease transmission among humans by investing in concrete grounds as opposed to the sand that is usually used in shacks and some favelas. Indeed, Nany et al.
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Chichakuri (Quechua chichaku, meaning chigoe flea (Tunga penetrans),R. García, Nombre Quechua de insectos peruanos, Nombre de algunos insectos y otros invertebrados en "Quechua", Renán J. García A., in: Revista Peruana de Entomología Vol. 19, W -(i)ri an Aymara suffix; Hispanicized spelling Chichacori) is an archaeological site in Peru consisting of stone tombs (chullpa), walls, houses and squares. The place was declared a National Cultural Heritage by Resolución Directoral Nacional No. 296/INC-2003 by the National Institute of Culture on May 16, 2003.
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For the most part, the chigoe flea lives 2–5 cm below sand, an observation which helps explain its overall distribution. The temperature is generally too hot for the larvae to develop on the surface of the sand and the deeper sand does not have enough oxygen. In a study of off- host stages, samples were taken from the top of the soil (to a maximum depth of 1 cm). The presence of T. penetrans in a soil sample was unaffected by soil temperature, air temperature or air humidity.
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If formaldehyde, chloroform, or DDT are used topically, care should be taken when dealing with the resulting morbidity. The T. penetrans flea can also be suffocated using occlusive petrolatum, while Vaseline will kill the organism as well, most likely due to suffocation as the stigmata would be covered. The gum of the mammee apple (Mammea americana), a fruit that also goes by the name Saint Domingo apricot, has also been used to kill the chigoe flea, though this has not been reported in the main T. penetrans literature. Even without treatment, the burrowed fleas will die within five weeks and are naturally sloughed off as the skin sheds.
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In this capacity she was in charge of rationing food and monitoring radio broadcasts. There continues to also be the allegation from fellow surviving guerrilla Benigno, that Bunke and Guevara had at some point become lovers in Bolivia; with Benigno remarking decades later in 2008 that "You could tell by the way they spoke so quietly and looked at each other when they were together near the end". Without Bunke as the guerrilla's contact to the outside world, the guerrillas then found themselves isolated. Bunke also soon found herself battling a high fever, a leg injury, and the painful effects of the Chigoe flea parasite.
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Tungiasis was endemic in pre-Columbian Andean society for centuries before discovery of T. penetrans as native to the West Indies. The first European description was published in 1526 by Gonzalo Fernández de Oviedo y Valdés, where he discussed the skin infection and its symptoms on crew members from Columbus's Santa Maria after they were shipwrecked on Haiti. Through ship routes and further expeditions, the chigoe flea was spread to the rest of the world, particularly to the rest of Latin America and Africa. The spread to greater Africa occurred throughout the 17th and 19th centuries, specifically in 1872 when the infected crewmen of the ship Thomas Mitchell introduced it into Angola by dumping of sand ballast, having sailed from Brazil.
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Tungiasis had been endemic in pre-Columbian Andean society for centuries before discovery of T. penetrans as native to the West Indies. The first case of tungiasis was described in 1526 by Gonzalo Fernández de Oviedo y Valdés, where he discussed the skin infection and its symptoms on crew members from Columbus's Santa Maria after they were shipwrecked on Haiti. Through ship routes and further expeditions, the chigoe flea was spread to the rest of the world, particularly to the rest of Latin America and Africa. The spread to greater Africa occurred throughout the 17th and 19th centuries, specifically in 1872 when the infected crewmen of the ship Thomas Mitchell introduced it into Angola by illegal dumping of sand ballast, having sailed from Brazil.
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