foot fetishist. chip sand [1945016penetrans] Tunga , here in a scanning electron microscope several days after penetration of the skin. The abdominal opening than on the right.
Eye of Science / Source
Where, exactly, is the sand flea have sex? On the dusty ground, where he spent the first half of his life? Or already nestled comfortably in his host, like a foot, where the man, he can suck the blood it needs to feed its eggs? The answer to this question that has long puzzled entomologists and experts of tropical health, seems to be the latter. A new study in which a researcher leaves a sand flea grow inside of his skin, concludes that the parasites copulate more likely when the females are already inside their hosts.
Tunga penetrans , also known as chigger flea, sand fleas, classy, jigger, nigua, picnic or pe of bicho, is widespread in the Caribbean, South America and Sub-Saharan Africa. The immature female digs permanently into the skin of a warm-blooded host, it also attacks dogs, rats, cattle and other mammals, where more than 2 weeks, it swells to many times its size original, reaching a diameter up to 10 mm. Through a small opening at the end of its abdominal cone, the insect breathes, defecates and expels eggs. The female usually dies after 4 to 6 weeks, always embedded in the skin.
Originally crew Caribbean, infected sand fleas sailing with Columbus on Santa Maria after they were shipwrecked on Haiti. They and others have brought the parasite to the Old World, where he eventually became endemic across sub-Saharan Africa. Even today, there is an occasional rider, showing in European and North American clinical journey in the feet of tourists who went barefoot on tropical beaches.
For people living in infested areas, however, the chip is a serious public health problem. What begins as a pale circle in the skin becomes red, then black, become painful, itchy and often infected, a condition called tungiasis. A chip seems to attract others, and people can be infested with dozens of both . The infection makes it difficult for people to walk and can lead to permanently deformed feet. There is no drug treatment; the only way to get rid of pests is to dig them. People often use unsterilised instruments to do this, which causes other infections, including tetanus. Tungiasis affects the poorest of the poor, says Jörg Heukelbach who studies the disease at the Federal University of Ceará, Fortaleza, Brazil, and is neglected and often misunderstood, even by health officials in endemic areas.
Marlene Thielecke, a Ph.D. student at the University of Medicine Berlin Charité, studying ways to prevent infection of tungiasis to Madagascar when she noticed that she was hosting a chip itself. As part of his job was to assess and record sand flea stages of development in the feet of the local villagers, she said, "I thought it might be interesting" to observe in its own foot. So she started taking photos and video regularly to keep track of what happened.
initially, the chip does not bother Thielecke and noted that he seemed to grow . But normally she soon realized he was not lying all unusual eggs for an integrated and mature otherwise apparently chip he also lived much longer than usual. after 2 months it was still regularly expels the fluid from his abdomen, a sign that he was still alive, but still no eggs. at this time, Thielecke said, the place was itchy, painful, and prevented him from walking normally. "I was getting uncomfortable" about leaving it in so long, she said, she extracted it.
A few months later, back in Berlin, she spoke with her supervisor comments to Charity tungiasis expert Hermann Feldmeier. Lack of eggs and exceptionally long life chip Thielecke was probably because he was never fertilized , said the researchers in a paper published this month in Medicine travel and infectious diseases . As soon as she found the chip, Thielecke started to wear socks and shoes to prevent other chip penetrate closed. ( "We were pretty," she said.) She and Feldmeier think maybe the chip has lived so long because he was in a sort of development "wait state," expect a male to find and fertilize its mature eggs.
that the chip was apparently virgin suggests an answer to the longstanding puzzle if the chips are fertilized before or after they incorporate. More than a century, researchers have reported observing the male coupling chips with disembodied female; others have argued that it is more likely than women to first integrate and are fertilized by males that find an infected mammal and mate with females integrated through its abdominal opening. (Males do not bite into the skin.) It would be logical evolution, says Feldmeier. Because women tend to integrate in clusters, everyone who comes will have a chance to mate with several females and a group of females will have a greater chance of being found by a man one.
overview of the sexual life of the chip has no immediate consequences for the fight against tungiasis in areas where it is endemic. But it could help doctors recognize the parasite in travelers returning home with a chip. Physicians should be aware that the individual chips "may not develop normally" and can live longer than manual predict, says Feldmeier.
And although one observation does not prove that women are still fertile after embedding, "it is very interesting," says Ingela Krantz, emeritus professor of infectious disease epidemiology at the University of Umeå Sweden. "this is the kind of knowledge that you usually go because you say sand fleas, they are a nuisance, we treat them." But to start from the beginning and try to understand these strange noise is important. "
For another icky tale of a scientist infected with the organism, he studies, see" Invasion of ticks nostril ".
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