A parasitic worm, Dirofilaria repens, lived in the face of a 32-year-old woman in Russia. (The New England Journal of Medicine)
First, it appeared as a small spot under the eye.
But for the next two weeks, the 32-year-old woman saw him move, taking pictures as he formed protrusions over his eye before it went down to his lip, forcing his mouth to swell.
He was a parasite – and he was living inside his face.
The case – and shocking images – were published Thursday in a report titled " Migrando Dirofilaria repens" in the New England Journal of Medicine, which details a case in which a woman of Russia became the host of a parasite through a mosquito bite. The report indicates that the woman, who was not identified, began to show symptoms after traveling to a rural area not far from Moscow, where she "remembered being frequently bitten by mosquitoes".
He experienced occasional itching and burning when the worm slid under his skin.
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Dirofilaria repens is a long parasitic larva that is transmitted by mosquitoes, according to the Centers for Disease Control and Prevention.
Dirofilaria are usually found in dogs or other carnivores, according to the CDC, but they are known to infest humans as well, especially in Europe and with certain species – D. repens D. tenuis and D. immitis (better known as heartworm in dogs).
How? Thomas Nolan, director of the clinical parasitology laboratory at the University of Pennsylvania School of Veterinary Medicine, said mosquitoes ingest microfilariae (the undeveloped embryos of the parasite), which then travel to the insect's intestine and mature in the first, second and third larvae in stage. The larvae make their way into the mouth parts of the mosquito and, according to Nolan, when the mosquito bites an animal – or human – they crawl quickly to the place of the bite.
Once in its new host, he said, the larvae mature into adult worms.
That's where things can get weird.
According to the guidelines of the European Society of Dirofilariosis and Angiostrongylosis (ESDA), Dirofilaria repens typically appears in humans near the eyes – "eyelids and under the conjunctiva (in which case the worm can be observed easily, sometimes actively moving), subcutaneous tissues (nodules) in the chest wall, upper and lower extremities, neck and in other regions of the body "such as the bads.  Occasionally, parasites can migrate to certain organs, such as the lungs, although it is less common, according to ESDA guidelines.
The lead author of the case report, Vladimir Kartashev, professor of the Department of Infectious Diseases at Ro Stov State Medical University in Rostov-na-Donu, Russia, said in an email on Thursday that such parasites are an "emerging disease" "in the western part of the former Soviet Union and in certain parts of Europe. He said that since 1997, more than 4,000 human cases have been reported in these countries, particularly in Russia and Ukraine.
The CDC declare D. repens – the species that the woman had in Russia – is not seen in the United States; another species, D. tenuis, has been reported in North America, but only in raccoons.
That said, parasites usually die on the skin and are easily eliminated.
The case report indicated that doctors in Russia surgically removed the worm from the woman's face, and she recovered. Well, at least physically.
She thought that the strange feeling was a lost eyelash. They were eye worms.
He ate raw fish almost every day, until a 5-foot-long tape slipped out of his body