Scientists find stronger evidence for link between cat faeces and schizophrenia

Imperial College, London ^ | Wednesday 18 January 2006 | Tony Stephenson

[Virginia-American]

Researchers have found stronger evidence for a link between a parasite in cat faeces and undercooked meat and an increased risk of schizophrenia.

Research published today in Procedings of the Royal Society B, shows how the invasion or replication of the parasite Toxoplasma gondii in rats may be inhibited by using anti-psychotic or mood stabilising drugs.

The researchers tested anti-psychotic and mood stabilising medications used for the treatment of schizophrenia on rats infected with T. gondii and found they were as, or more, effective at preventing behaviourial alterations as anti-T. gondii drugs. This led them to believe that T. gondii may have a role in the development of some cases of schizophrenia.

Dr Joanne Webster from Imperial College London, and lead researcher said: "Although we are certainly not saying that exposure to this parasite does definitely lead to the development of schizophrenia, this and previous studies do show there may be a link in a few individuals, providing new clues for how we treat toxoplasmosis and schizophrenia."

Previous epidemiological and neuropathological studies have indicated some cases of schizophrenia may be associated with environmental factors, such as exposure to the parasite T. gondii. At the same time several of the medications used to treat schizophrenia have been shown to posess anti-parasitic and in particular anti-T.gondii properties. This led the authors to suspect that the anti-psychotic activity of these medications may be due to their inhibition of these parasites.

When the rats were given Haloperidol, an anti-psychotic, and Valporic acid, a mood stabiliser, the behavioural symptoms of T.gondii were reduced. They found the drugs were able to limit the suicidal feline attraction by which the rats became less aware of the dangers of cats.

Dr Joanne Webster added: "By showing that drugs used to treat schizophrenia affect the parasite T. gondii, this does provide further evidence for its role in the development of some cases schizophrenia. It may be that anti-psychotic drugs work partly by parasite inhibition, and this could lead to new medicine and treatment combinations."

The researchers have already begun human clinical trials using anti-T. gondii treatments as adjunct therapies for schizophrenia with researchers at Johns Hopkins University.

Notes to editors:

1. Parasites as causative agents of human affective disorders? The impact of anti-psychotic, mood stabiliser and anti-parasite medication on Toxoplasma gondiis ability to later host behaviour, Procedings of the Royal Society B.

2. Consistently rated in the top three UK university institutions, Imperial College London is a world leading science-based university whose reputation for excellence in teaching and research attracts students (11,000) and staff (6,000) of the highest international quality. Innovative research at the College explores the interface between science, medicine, engineering and management and delivers practical solutions that enhance the quality of life and the environment - underpinned by a dynamic enterprise culture.

[Virginia-American]

A friend sent me a link to this blog, The Return of the Puppet Masters by Carl Zimmer, which gives some of the background for this article. (The Proc. Royal Society is only accessible by subscription.)

Normal rats shy away from places that smell like cats; infected ones like cat odor. This makes them more likely to be eaten, which puts the parasite in cats, which shed it to be eaten by rats....

[atomicpossum]

How many cats does Howard Dean have, anyway?

[wjersey]

Does this explain the nutty women with 100 cats?

[Slings and Arrows]

[ozzymandus]

Is this why my dog is crazy?

[Virginia-American]

Not a crevo thread, exactly, but an interesting bit of natural history and medicine.

Who'd have thought that antipsychotic and antiparasitism drugs are, to some extent, the same?

Would you please ping your smaller list?

Is there a medicine ping list?

[redheadtoo]

Researchers have found stronger evidence for a link between a parasite in cat feces...and an increased risk of schizophrenia.

Now why couldn't this study come out earlier? When I was a kid my mother used to make me clean the litter box. I could have used it as an argument as to why I should be excused from the unpleasant task.

[NaughtiusMaximus]

I don't really buy into this explanation.

And if you don't believe me, ask the giant cockroach in the corner.

Sorry, only doing what the voices tell me.

[PatrickHenry]

Would you please ping your smaller list?

Truly a revolting topic. I'll ping, but it may not be the list you want.

[Lady Jag]

Does this explain the nutty women with 100 cats?

The voices told you that.

[Fawn]

I think it's the chicken or the egg theory.
Anyone who touches cat poo must already be schizo.
I've had cats my whole life...inside and out and can't remember once where I had come into actual contact with cat poo. On the other hand-- dog and bird poo have made their way to my body on several occasions.
This is a crap article.

[PatrickHenry]

Cat Faeces Ping List Don't ask to be added to or dropped from this list; I know what you like.

[Lady Jag]

British origination, low credibility.

Most Schophrenics in the US are males 18-25, the least likely group to have cats.

Rat contact, perhaps, but that would make NYC the schizo capital of the world (which, believe it not, it is not).

[b_sharp]

You know, I'd participate in this thread but I have to run down and clean out the two cat litter boxes.

If anyone wants me to mail them a bit'o cat feces, just freepmail me your address.

[LibFreeOrDie]

Most Schophrenics in the US are males 18-25, the least likely group to have cats.

Pregnant women used to be warned to stay away from cat litter boxes, for fear of the toxoplasmosis. Could schizophrenia (in some cases) be a result of prenatal exposure?

[To Hell With Poverty]

Crap. Looks like us kitty-pingers could be in deep doo-doo.

[furball4paws]

Personally, I'm a dog person.

In school I learned that cats carry more parasites transmissable to humans than any other domesticated animal. This dude, Toxoplasma is one nasty piece of work.

[gogogodzilla]

Only if the expectant mothers kissed cat butt?

Hmmm, just one more reason to avoid eating cat poop. The other is that the bird flu can be spread through eating it as well.

See this thread:

http://www.freerepublic.com/focus/f-news/1561985/posts


So it's looking like the real name of Pestilence, one of the horsemen of the Apocalypse, is really 'cat poop'.

:-)

[AmericaUnite]

I was going to post the estimated percent of humans who have been exposed to Toxoplasmosis. I'm sure country to country it's different. But I found this:
http://www.amcgltd.com/archives/cat_science.html
"Crazy Rats

New Scientist is carrying this report discussing new discoveries related to toxoplasmosis, cats, rats, and human schizophrenia:

Antipsychotic drugs can limit the behavioural abnormalities associated with a parasitic infection called toxoplasmosis in some rats – the condition causes them to become “suicidally” attracted to cats. The findings provide insight into a possible cause of schizophrenia, say the researchers behind the new study.

While the article's author does throw in a reference to everyone's favorite cat-blamer E. Fuller Torrey, the authors of the study take pains to point out in no way are they trying to implicate toxo infections as a cause of schizophrenia. From the article, it would appear more likely that the toxo parasite perhaps does something that manipulates at least some of the same brain areas, causing a disease which is quite similar. A subtle difference, but quite important for future research.

Plus the whole concept of a parasite that tricks its host into becoming attracted to a specific kind of predator just to complete its life cycle is just amazing. Sounds like something out of a Star Trek episode."

[teenyelliott]

Interesting.

My grandmother was schizophrenic, and hated cats. She spent the last ten years of her life extremely ill, and died at 91.

My grandfather, on the other hand, loved cats and always had them. He was healthy as a horse until he died at 104 (and he smoked his own hand rolled cigs and enjoyed his whiskey, health freaks).

My theory based on actual events; if you don't have cats, you don't live as long. :)