Cat Poop Parasite Controls Minds Early And Permanently, Study Finds

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Cat Poop Parasite Controls Minds Early And Permanently, Study Finds By Maggie Fox Sep 18 Even after infection with Toxoplasma gondii has been removed from rodents' brains, they continue to behave as if unafraid of the smell of cat urine, suggesting that the infection causes long-term changes in the brain.

Wendy Ingram and Adrienne Greene

Even after infection with Toxoplasma gondii has been removed from rodents' brains, they continue to behave as if unafraid of the smell of cat urine, suggesting that the infection causes long-term changes in the brain. A parasite that changes the brains of rats and mice so that they are attracted to cats and cat urine seems


to work its magic almost right away, and continues to control the brain even after it’s gone, researchers reported on Wednesday. The mind-controlling parasite, called Toxoplasma gondii, might make permanent changes in brain function as soon as it gets in there, the researchers report. They aren’t sure how yet. “The parasite is able to create this behavior change as early as three weeks after infection,” says Wendy Ingram of the University of California, Berkeley, who worked on the study. T. gondii has captured the imaginations of scientists and cat lovers ever since it was learned it can control the behavior of rodents. It changes their brains so they lose their innate fear of the smell of cat urine. In fact, it precisely alters their fear reaction so that they love the smell of cat pee.

This makes infected rodents much more likely to be caught by cats, which eat them and their mindcontrolling parasites. T. gondii can only reproduce in the guts of cats, so its behavior directly affects its own survival. It doesn’t just affect cats. People can be infected too -- pregnant women are told to stay away from cat feces for this very reason. It normally doesn’t bother people, but it can cause brain inflammation, called encephalitis, in some -- especially those with compromised immune systems like pregnant women.


“More than 60 million men, women, and children in the U.S. carry the Toxoplasma parasite, but very few have symptoms because the immune system usually keeps the parasite from causing illness,” the Centers for Disease Control and Prevention says on its website. Chronic infection with the parasite Toxoplasma gondii can make mice lose their innate, hard-wired fear of cats. Studies have linked toxoplasmosis with a range of human mental diseases, including schizophrenia, bipolar disease, obsessive compulsive disorder and even clumsiness. This study doesn’t answer questions about people, Ingram points out. “It does not necessarily explain crazy cat ladies or why there are LOLCATS online,” she says. But it does begin to hint at a potential mechanism for how and when the parasite changes the mouse brains. “I want to know how the behavioral change is happening,” Ingram says. Her team used a specially genetically engineered version of the parasite, made by a team at Stanford University. Normal T. gondii parasites form a cyst in neurons. “It was assumed that the cysts … were doing something biologically that is actively changing the behavior,” Ingram told NBC News. But the genetically engineered parasite wasn’t able to make cysts. And it was so weak that the rats’ immune systems were able to clear it from their brains. But even so, rats infected with this weakened form of the parasite just loved the smell of cat urine, Ingram and colleagues report in the Public Library of Science journal PLoS ONE. “This suggests the parasite is flipping a switch rather than continually changing the behavior,” says Ingram. She suspects it’s somehow activating the immune system in a way that then alters brain function. “That’s one of the very first things I am going to be checking,” Ingram says.

Toxoplasmosis From Wikipedia, the free encyclopedia Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii.[1] The parasite infects most genera of warm-blooded animals, including humans, but the primary host is the felid (cat) family. Animals are infected by eating infected meat, by ingestion of feces of a cat that has itself recently been infected, and by transmission from mother to fetus. Cats are the primary source of infection to human hosts, although contact with raw meat, especially lamb, is a more significant source of human infections in some countries. Fecal contamination of hands is a significant risk factor.[2]


Up to a third of the world's human population is estimated to carry a Toxoplasma infection.[3] [4] The Centers for Disease Control and Prevention notes the overall seroprevalence in the United States as determined with specimens collected by the National Health and Nutritional Examination Survey (NHANES) between 1999 and 2004 was found to be 10.8%, with seroprevalence among women of childbearing age (15 to 44 years) 11%.[5] Another study placed seroprevalence in the US at 22.5%.[4] The same study claimed a seroprevalence of 75% in El Salvador.[4] Official assessment in Great Britain places the number of infections at about 350,000 a year.[6] During the first few weeks after exposure, the infection typically causes a mild, flu-like illness or no illness. However, those with weakened immune systems, such as those with AIDS and pregnant women, may become seriously ill, and it can occasionally be fatal.[7] The parasite can cause encephalitis (inflammation of the brain) and neurological diseases, and can affect the heart, liver, inner ears, and eyes (chorioretinitis).[8] Recent research has also linked toxoplasmosis with attention deficit hyperactivity disorder, obsessive compulsive disorder, and schizophrenia.[9] Numerous studies found a positive correlation between latent toxoplasmosis and suicidal behavior in humans.[10][11][12] Charles Nicolle and Louis Manceaux first described the organism in 1908, after they observed the parasites in the blood, spleen, and liver of a North African rodent, Ctenodactylus gundi. The parasite was named Toxoplasma gondii, from the Greek words τόξον (toxon, "arc" or "bow") and πλάσμα (plasma, "creature"), and after the rodent, in 1909. In 1923, Janku reported parasitic cysts in the retina of an infant who had hydrocephalus, seizures, and unilateral microphthalmia. Wolf, Cowan, and Paige (1937–1939) determined these findings represented the syndrome of severe congenital T. gondii infection.[2] READMORE


Infecting A Snail: Life Cycle Of The Grossest Parasite By Thomas Hayden 05.24.10 From barnacles that hijack crabs to a protozoan that makes rodents cozy up to cats, parasites do a lot more than make you puke. But for sheer gross-out glory, it’s hard to beat Leucochloridium paradoxum. These flatworms live in birds’ rectums, and they give garden snails a glimpse of hell. 1/ A grazing snail eats a bird dropping. Gross, right? Well, what’s even grosser is that the dropping is filled with parasite eggs. Garden snails can’t digest the eggs. They survive their trip through the snail’s tummy intact and spread to nearby organs. 2/ The invading Leucochloridium runs through a couple of life-cycle stages before landing in the snail’s hepatopancreas, the organ that passes for its liver-pancreas-thing. 3/ The parasite pumps embryo after embryo into fat, throbbing brood sacs it builds in the snail’s eyestalks. 4/ An intelligent designer might have stopped at systemic infection and pulsating, brightly colored tentacles. Not evolution, though. Evolution goes up to 11. The parasite takes control of the snail’s rudimentary brain, making the mollusk forget that it’s scared of daylight and spurring it to inch out into the open. 5/ To us, the infected tentacles look like a fleshy, Cronenbergian nightmare. To birds, they look like delicious caterpillars. 6/ The birds eat the eyestalks and get infected by the parasites, which reproduce and lay eggs in the bird’s rectum, ready to be deployed in future poop. 7/ Even if the snails survive the destalking, they stay parasitized—which means they can infect other birds, which can infect other snails. It’s the circle of life. SOURCE Cat poop parasite controls minds early – and permanently, study finds http://www.nbcnews.com/health/health-news/cat-poop-parasite-controls-minds-earlypermanently-study-finds-f4B11194722 SOURCE Infecting a Snail: Life Cycle of the Grossest Parasite http://www.wired.com/2010/05/process_snail/

INFOWARS.COM BECAUSE THERE'S A WAR ON FOR YOUR MIND


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