Mind Control Parasites in Half of All Humans

iiii writes "According to a Yahoo News story, half of the world's human population is infected with Toxoplasma, a parasite shown to alter the brain function of rats, inducing them into behavior that benefits the parasite but is suicidal for the rat. So what affect does it have on humans? Article comes complete with Heinlein 'Puppet Masters' reference. I call dibs on using Toxoplasma as a name for my rock band."

Comments

Name taken

[lysergic.acid]

There's already a German punk band called Toxoplasma.

Re:Name taken

[lysergic.acid]

So Toxoplasma triggers the production of LSD in the host organism's brain, and this is believed to be a major cause of schizophrenia in humans? Are there any other sources that support this claim? LSD is somewhat difficult to test for in humans, and even then the link between schizophrenia and LSD is a rather contentious subject in the medical community. The article itself also seems to question the verity of this hypothesis:

"A word of caution: our authors' impressive theoretical edifice is built on some pretty thin evidence. It's simplistic to say T. gondii works by triggering the production of LSD--among other problems with the idea, acid mainly gives rise to visual hallucinations, whereas the delusions of schizophrenics are primarily auditory (e.g., hearing voices)."

As you can probably guess, I am a big fan of acid and psychedelics in general. I've taken many psychedelic drugs, including but not limited to: Cannabis, LSD, Psilocybin Mushrooms, Mescaline, MDMA, AMT, 2C-E, 2C-I, 2C-B, 2C-T-7, 5MeO-AMT, 5MeO-DiPT, Ketamine, DXM, LSA, Salvia, and many others. I've taken traditional psychedelics (Tryptamines and Phenethylamines such as LSD, Psilocybin, Mescaline, MDMA, 2C-*, 5MeO-*, etc.), dissociatives (PCP, DXM, Ketamine, Nitrous, Salvia, etc.), and even deliriants (Dramamine, Datura, Amanita Muscaria, Bella Donna, etc.) on occasion, so I'm pretty well-versed in the various categories of psychedelic drugs and their effects.

Out of the 3 main categories of psychedelic drugs, I would say that the most dangerous is probably the deliriants, typically anticholinergenic deliriants. Strong dissociatives such as PCP may induce prolonged psychotic states, possibly even causing long-term brain-damage with chronic exposure, but they are unlikely to cause full-blown hallucinations as with anticholinergenic drugs. Conventional psychedelics such as LSD, pot, Mushrooms, Mescaline, etc. are even less likely to induce psychotic/delusional episodes compared to strong dissociatives like PCP. Typically, people on traditional psychedelics such as acid may see OEVs(opened eye visuals) or CEVs(closed eye visuals) but they are not hallucinations in the strict sense. They are more accurately described as perceptual illusions, such as moving patterns, altered spatial perception, synesthesia, etc. Only deleriants cause full-blown hallucinations that one can't distinguish from reality. This is why there is a very high incidence of "bad trips" on deliriants, many of which resulting in ER visits or stays in the psychiatric ward.

While I don't doubt that a bad trip on acid can be the springboard for schizophrenia, these are usually cases where the individual is already predisposed towards mental illness, and the acid simply triggers it by inducing a traumatic experience. Most people, however, walk away from their bad trips relatively unscathed. Some naive users may continue to be haunted afterwards by embarassing things they did while they were tripping, but few suffer any long-term psychological effects from their bad trips.

I have simply known too many people who have done acid or similar hallucinogens and have never exhibited any psychotic behavior to believe that LSD can cause schizophrenia. In fact, I don't think that LSD plays much of a role in the etiology of schizophrenia or any other mental illness. It's more likely that most people who develop schizophrenia after taking LSD would have still developed the mental disorder eventually even if they hadn't taken any drugs.

I've only met 3 individuals whom I've witnessed really bizarre behavior from after they took psychedelic drugs. One appeared to experience acute psychotic episodes after smoking pot or drinking alcohol, but this seemed to be due to his being socially maladjusted more than anything. The second individual behaved very strangely after consuming mushrooms on 2 different occassions, but otherwise he was perfectly normal even when he smoked weed or

Re:Welcome...

[packeteer]

http://www.guardian.co.uk/life/thisweek/story/0,12 977,1048642,00.html

Dated Thursday September 25, 2003

Ive read that these parasited are more common in the UK or perhaps we only know of more cases there becuase people are looking harder. Im not exactly an expert on the topic but i know this has been "news" for years now.

More discussion of toxoplasma

[rdwald]

Cecil Adams wrote a article discussing toxoplama's effect on birth defects and schizophrenia, including the possibility that toxoplasma floods the human brain with LSD.

Re:ALIEN PARASITES ENSLAVE HUMANS!

[BarryNorton]

"T. gondii may cause schizophrenia and may do so by producing or triggering the production of an hallucinogenic chemical" ('Genes, Germs, and Schizophrenia: An Evolutionary Perspective', Ledgerwood et al, Perspectives in Biology and Medicine 46(3):317-48, 2003).

But, hey, why keep up with current research (at least via credible objective surveys in reputable journals) when you can just read Wikipedia?

Re:Welcome...

[alicenextdoor]

Toxoplasma gondii is a protozoan which has cats as its definitive host. It has a wide range of intermediate hosts, and is capable of infecting all warm-blooded vertebrates, including humans. Toxoplasma lives inside the epithelial cells lining the intestine of its feline host. Eggs are shed with the faeces, and can survive in soil for several months. Toxoplasma cells can also penetrate work their way out of the intestine and infect almost any other cell type, eventually forming cysts in the host's brain, liver and muscles. Intermediate hosts are infected either by eating food or water contaminated with infected cat faeces; by eating undercooked meat from other intermediate hosts containing Toxoplasma cysts; or, in the case of some unfortunates, via the placenta from an infected mother.

Back to the rats. Rats are easily infected with Toxoplasma, and have been the subject of a lot of experimentation. Infection tends to lead to the establishment of Toxoplasma cysts in the brain, and alteration of the rat's behaviour. Infected rats tend to be more active and less afraid of novelty, both of which behaviours are likely to place the rat at increased risk of predation by cats. The changes go further than that, however. Rats are inherently, and understandably, afraid of the odour of cats. Even lab rats which have not been exposed to cats for generations will avoid areas marked with cat urine. Toxoplasma infected rats do not, however, share this aversion; in fact, rats tested in pens marked with different types of scent (rat urine, cat urine, rabbit urine and water) actually seemed to be suicidally attracted to the cat-scented areas . The infected rats appeared to be completely healthy in all other ways .

The implications of this research are enough to send a frisson of fear down the spine of anyone, devoted parasitologist or otherwise. Toxoplasma infection is common amongst humans. It has been estimated that 30% of the global human population may be infected, with prevalence in specific countries ranging from 22% in the UK to 84% in France. Can the parasite affect human behaviour in the way in which it affects that of rats? The answer appears to be "yes". One manner in which this happens is via direct damage to the host's brain and central nervous system. Babies born to mothers infected with Toxoplasma early in fetal development can suffer from widespread disease, including mental retardation . Infection later in development can lead to a persistant infection with no apparent symptoms, with the parasite forming cysts in the brain. With any luck the immune system can keep the parasite under control; depression of the immune system, however, can result in its reactivation, with consequent neurological or psychiatric effects.

It has also been suggested that prenatal exposure to toxoplasmosis can increase an individual's susceptibility to schizophrenia , but because of the difficulty of experimenting in this area, there is little supporting evidence , although it is interesting to note that several of the drugs used in the treatment of schizophrenia and bipolar disorder inhibit the replication of Toxoplasma . Does the manipulation hypothesis hold in humans? If it does, it must be only as a non-adaptive side effect of the ability to manipuate hosts such as mice and rats, since, as Joanne Webster points out in a fascinating review article on the subject , humans are rarely preyed upon by cats. There does appear to be some evidence that human personality traits are affected by Toxoplasma infection, but the one study that has specifically looked for an effect is less than wholly convincing. Flegr and Hrdý, found that men with chronic Toxoplasma infections had a greater tendency to disregard rules and were more suspecting, jealous and dogmatic than non-infected controls . However, the number of males tested was only 195, of whom 56 were infected, and the effect disappeared entirely if the male and female subjects were analyzed together. This research provides a fascinating, if somewhat disturbing, hint of an effect, but it seems safe to say that most of us are more than mere parasite-controlled robots.

Re:Half infected?

[porcupine8]

This connects well with the known etiology of toxoplasmosis, and is why the MD tells your pregnant wife/girlfriend/mom to stay away from cats.

Specifically, cat poop. Sorry, it may sound like nit-picking to you, but you should see the number of cats who wind up in shelters because their owner got pregnant. Pregnant women do NOT need to stay away from cats - they just need to stay away from the litter box. They shouldn't clean it, and should avoid inhaling dust from it. If your cat has something wrong with it and can't clean its bum properly, someone (who's not pregnant) should be keeping it clean for them. Only single pregnant women with no one to take care of this stuff for them might need to actually rehome their cats - and they can usually wear gloves and a surgical mask when cleaning the litterbox.

Toxoplasma and Car Accidents

[Valdrax]

Actually, there is another hypothesized threat from Toxoplasma gondii that is a deadly risk even for people with just a dormant infection. (Toxoplamsa doesn't get eliminated by the immune system; it just goes dormant in cysts in the muscle tissue and brain and continues to effect its host for life.)

Latent toxoplasmosis seems to give people a significantly higher risk of getting in a car accident than people who do not have it. People with latent toxoplasmosis have slower reaction times and a tendency towards more risk-seeking behavior than people without, just like rats with the disease.

No, that's not true

[maynard]

There are numerous studies which indicate that latest T. gondii cyst infection produces a noticeable drop in motor skills and intelligence. I wrote an article on this over at K5 a couple weeks ago. One of the comments linked to a study which showed a significant increase in risk of traffic accidents for those with latent T. gondii infection.

However, the notion that this is a "mind control" parasite in humans is completely off base. A previous study showed that mice infected with T. gondii had increased risk of cat predation. Researchers believe that may be caused by increased dopamine levels in mouse brains as a result. But that is still speculative.

I could add that I submitted this story to /. almost three weeks ago and was rejected within an hour... but that would be off topic.

Cat "poop"

[QuaintRealist]

I get your point, and love my cat, too, but the precautions need to be a bit more than you make out. Cats who "clean up" themselves by licking the fur around their rectum just push the infectious material around their fur. After the saliva dries, T. gondii remains infectious for some time afterwards. Really, pregnant women should wash their hands after handling cats.

That said, nobody should "re-home" an animal just because they're too lazy to take a little extra effort for 9 months, unless you're talking about "re-home" as in "here mom, take care of my cat for a few months and I'll take her back".

I do understand that the chance of becoming infected is low. It's important too to acknowledge that the damage of infection is catastrophic. (Pun fully intended)