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The Amoeba That Eats Human Intestines, Cell By Cell

Posted by samzenpus on from the break-out-the-pepto dept.

sciencehabit (1205606) writes "Entamoeba histolytica is a tiny pathogen that takes a terrible toll. The single-celled parasite—an amoeba about a tenth the size of a dust mite—infects 50 million people worldwide and kills as many as 100,000 each year. Now, a new report reveals how the microbe does its deadly damage: by eating cells alive, piece by piece. The finding offers a potential target for new drugs to treat E. histolytica infections, and it transforms researchers' understanding of how the parasite works."

71 comments

  1. treatment by Anonymous Coward · · Score: 0

    So how do you treat it?

    1. Re:treatment by fuzzyfuzzyfungus · · Score: 5, Interesting

      I'm not a tropical medicine expert or anything (and even if I claimed to be, would you trust a guy who impersonates an opinionated fungus on the internet recreationally?); but according to Our Wiki Overlords, corroborated by assorted googling, the current treatements of choice appear to be a number of antiprotozoal drugs found to work against this organism; but nothing particularly specific to it, and definitely nothing that targets the specific genetic and chemical pathways the ameoba exploits to achieve the 'nibbling' attack. Again, nonexpert here; but the use of a grab-bag of nonspecifics suggest that it hasn't (yet) done anything brutally clever in terms of drug resistance; but that existing understanding of the organism probably hadn't provided any really elegant attacks against this organism in particular, leaving 'probably best to use stuff that works on protozoa, since it is one.' as the standard.

      The researchers did experimentally disrupt this process(once with a drug, in a second case with a genetically crippled ameoba strain) as part of demonstrating that the 'nibbling' was the mechanism behind human cell death(which can apparently cause some ghastly intestinal trouble), so presumably there is some hope that we'll be able to weaponize the mode of attack they used, and get an elegant, selective, unlikely-to-interfere-with-other-eukaryotes-like-the-patient, drug that will prevent the horrible-death-by-intestinal-nibbling; but nothing in pill form just yet, certainly not that you could just go shoving into patients without killing some little fuzzy animals first.

      (Also, if Malaria is anything to go by, the statistical answer to 'how do you treat it?' is 'On average, you don't. Protozoa are tough motherfuckers and it mostly just kills poor people in ghastly countries anyway. Let's go find a cure for hair loss and midlife limp-dick syndrome...')

    2. Re:treatment by Anonymous Coward · · Score: 3, Interesting

      They had a show on tv called 'Monsters Inside Me' the show is about parasites that invade the human body. They also show how doctors seem to fail, or use their educated minds keep the diagnosis simple. They also show or describe the treatment.. And it is what you'd expect just use antibiotics, or antiprotozoal drugs.
      Sarcasm, what could possible go wrong with that? History tells us something but we continue to go ahead with using those drugs.

      Something that should be universal in health care are running tests for parasites, I really wonder how many people are being forced to go thru terrible treatments for something like cancer, or pick another illness, when it was a parasite, another failure of the medical system. Parasites have been around as long if not longer then the flu, and yet there isn't a mandatory test. Whether it is a check up or an emergency.

    3. Re:treatment by Luckyo · · Score: 2

      The normal approach to parasitic treatment is to give patient drugs that are highly toxic to the parasite and much less so to the host.

    4. Re:treatment by gregor-e · · Score: 4, Funny

      We should develop a drug that gives them a liking for the taste of their own kind while disliking the taste of humans. Maybe call it ouroborosin?

    5. Re:treatment by khallow · · Score: 2

      (Also, if Malaria is anything to go by, the statistical answer to 'how do you treat it?' is 'On average, you don't.

      The statistical answer is drain the swamps, kill the mosquitoes, and malaria goes away. There's a reason malaria no longer has a presence in the developed world and it's not because nobody cared about it.

    6. Re:treatment by tlambert · · Score: 1

      Be like a first-worlder, and have less tasty intestines.

    7. Re:treatment by treeves · · Score: 2

      But isn't "draining the swamps" now called "wetlands destruction", so people don't want to do it?

      --
      ...the future crusty old bastards are already drinking the Kool-Aid.
    8. Re:treatment by Anonymous Coward · · Score: 0

      Aren't specific viruses the scourge of protozoa?

    9. Re:treatment by Opportunist · · Score: 2

      Well, parasites have become the zebras of today's medical zoo. While it was very common in the good ol' days of yore when it was pretty much a given that you'd have some sort of parasites in you (quite literally to the point where it was a surefire way to tell that something's wrong with you if you did NOT have the "normal" collection of parasites in you), parasites have become something rather rare in our highly sterilized world with through screening of food and other stuff that we put on or into us. Hell, even eating sushi in areas that are days away from any coast is not the food equivalent of playing Russian Roulette.

      It is simply far more likely that you have some kind of bacterial disease or even cancer rather than some odd parasite.

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
    10. Re:treatment by Anonymous Coward · · Score: 0

      Yes, all that malaria in the swamps of Florida and Louisiana are really debilitating though...

    11. Re:treatment by Anonymous Coward · · Score: 0

      We can't do that. It might go out of control and saturate the globe. Completely.

    12. Re:treatment by butalearner · · Score: 1

      Ouroborosin would make them eat themselves, which is a whole other thing. The drug you're describing would probably be called cannibalis. I can just see the tagline: "Cannibalis: giving parasites a different kind of the munchies."

    13. Re:treatment by SJester · · Score: 1

      ...a guy who impersonates a recreational fungus on the internet opinionatedly... FTFY

    14. Re:treatment by Anonymous Coward · · Score: 0

      limp dick ain't no joke

    15. Re:treatment by khallow · · Score: 1

      Or Washington DC for that matter. I can't think of a better city to build in a swamp.

    16. Re:treatment by unclefred · · Score: 1

      This Amoeba is like a tank,uncomplicated and ugly but it gets the job done and is hard to stop becalms it doesn't have any obvious fatal weaknesses so any powerful concoction designed to blast it's way through this biological Tank will hurt the host as well unless tightly targeted at the Amoeba.so as to avoid collateral damage. The other possibility(although an ugly one) is that drug companies are not in a hurry to find a cure because this problem occurs in low social economic populations who desperately need their help but can't pay for it so big Pharma drags its feet and decides to find a cure for cellulite instead because its more profitable. Welcome to the 21st Century a sweet romantic place...........

  2. I for one... nevermind by retroworks · · Score: 1

    This is like the Animal channel bugs that infest you program.

    --
    Gently reply
  3. -heave- by onproton · · Score: 1

    I was eating but, hey who needs food.

    1. Re:-heave- by Anonymous Coward · · Score: 0

      Bulimia: twice the taste, none of the calories.

  4. infects 50 million, eh? by Cthefuture · · Score: 5, Interesting

    Infects 50 million and kills 100000... I'll take those odds. Better than driving to work for a year.

    --
    The ratio of people to cake is too big
    1. Re:infects 50 million, eh? by fuzzyfuzzyfungus · · Score: 4, Interesting

      The major nuisance with those odds (even if the nonkilled are all aymptomatic, rather than variously sickened) is that it means the organism can remain in the population basically forever, with an ample supply of carriers, barring develpment of some persistent eradication mechanism so effective and safe that it can ethically be mass-applied as a largely preventative measure(as, for instance, with the polio vaccine, where the safety and efficacy are good enough, and the duration of effect long enough, that you can just blanket entire areas with vaccination campaigns until the organism disappears from the population).

    2. Re:infects 50 million, eh? by hawkeyeMI · · Score: 5, Informative

      I'm guessing you haven't had amoebic dysentery. It saps all your energy and makes you poop blood. I'll take driving to work, thank you.

      --
      Error 404 - Sig Not Found
    3. Re:infects 50 million, eh? by Anonymous Coward · · Score: 4, Interesting

      Kills 100,000 *per year.* So, each year it kills 1 in 500 people that have it. That's very roughly a mortality rate of over 10% (rough math: of 500 people that have it now, approximately 50 of them will be dead from this after 50 years, and approximately 400 of them will be dead from other causes (with about 50 still alive)).

      Much less than 10% of the people who decide to drive to work during the course of their lifetimes are killed by driving to work.

      In the US in 1972, there were about 200 million people, and about 50 thousand of them died in traffic fatalities (about 2.5% of all US deaths that year). This was the worst year for traffic fatalities by volume and the eighth worst by percent. Let's say that roughly one quarter of the people in the US at the time displayed the symptoms of "driving to work" that year. Even if we presume that all of the traffic fatalities that occurred that year were due to driving to work, that's still a mortality of half of this mortality rate. We would need to suggest that only 1/8 of the population of the US drove to work that year to get to the same mortality rate as this pathogen.

      And that's the worst year for traffic fatalities in US history. Since then, our population has increased 50%, and traffic fatalities have decreased 40%. And once again, this is all using a worst case scenario of every traffic fatality being caused by driving to work, rather than driving for any other reason.

      So no, having this pathogen is *not* better than driving to work...these are not odds you would take.

    4. Re:infects 50 million, eh? by hawkeyeMI · · Score: 1

      Oh and I forgot, at least one treatment for it, Flagyl, actually makes you feel worse. But at least then you're done and can stop taking it.

      --
      Error 404 - Sig Not Found
    5. Re:infects 50 million, eh? by KingOfBLASH · · Score: 1

      Oblig xkcd:

      http://xkcd.com/558/

    6. Re:infects 50 million, eh? by Anonymous Coward · · Score: 1

      I believe a better car analogy to make your point would be, x number of people get in car accidents and y die as a result. Your analogy of comparing the ratio of drivers to driving deaths is missing a step.

      In this case the rate of infection is .7% for the entire world. The chance of death is .0014%. This does not even take into account first world healthcare. With your analogy, using your numbers, the death rate by car accidents in the current year is .01%. Driving to work is seven times more deadly than this amoeba before discounting for first world standards such as sanitation and healthcare.

      Moving on to the better analogy, in 2010, 5.4 million car crashes were estimated with .0328 million dying (first results on google). So the odds of death once the 'symptoms' of crashing has occurred is .6%. The odds of dying by this amoeba once infected is .2%. In this more accurate analogy, getting in an accident is three times more deadly. Again, ignoring first world standards.

      Digging deep, the rate of infection in the US appears to be 13.5 diagnoses per 10,000 person-years. Running the numbers again, the death rate in the US assuming the same death rate as worldwide becomes .00027%. Given that, driving is 37 times more dangerous than this amoeba.

      So which is it? Driving is seven times, three times, or 37 times more deadly? It depends on which view you choose to use. Since the outcome is the same in this case, your choice does not matter much.

    7. Re:infects 50 million, eh? by Anonymous Coward · · Score: 0

      Infects 50 million and kills 100000... I'll take those odds. Better than driving to work for a year.

      You're saying 1 in 500 people a year dies driving to work where you live? Damn man, where do you live?

    8. Re:infects 50 million, eh? by stoploss · · Score: 1

      Oh and I forgot, at least one treatment for it, Flagyl, actually makes you feel worse. But at least then you're done and can stop taking it.

      As a bonus, while you're on Flagyl you can't even drink to forget your problems.

    9. Re:infects 50 million, eh? by Anonymous Coward · · Score: 2, Informative

      I had this (stayed in some slums in tropical areas where the water supply comes from a deep-well 5 meters down, meanwhile the toilet buries the shit in sand 2 meters down. . . so shit has 3 meters to turn back into water. . . usually this works surprisingly well!).

      Anyway, treated it goes away fairly quickly, even with the current non-specific medicines (though these are powerful antibiotics and will wipe out *all* of the good stuff with the bad. . . this can have serious consequences for some).

      Untreated, you're in for a year of fever and shitting blood before you'll eventually clear it (maybe staying a carrier) and develop immunity.

    10. Re:infects 50 million, eh? by Anonymous Coward · · Score: 1

      It saps all your energy and makes you poop blood.

      Sounds just like my last car.

    11. Re:infects 50 million, eh? by geezer+nerd · · Score: 1

      My grandfather had amoebic dysentery for years. It left him a debilitated husk when he died in 1956.

      Apparently he acquired the infection when drinking stream water while hunting for food for his family sometime during the 1920s. There was no effective treatment back then, so he just suffered.

      Not particularly something to have fun with.

    12. Re:infects 50 million, eh? by Anonymous Coward · · Score: 0

      Oh and I forgot, at least one treatment for it, Flagyl, actually makes you feel worse. But at least then you're done and can stop taking it.

      As a bonus, while you're on Flagyl you can't even drink to forget your problems.

      Oh, so instead of rotting the intestines we instead choose to rot the liver, logic!

    13. Re:infects 50 million, eh? by Anonymous Coward · · Score: 0

      No. Your GP's choice was *driving* versus getting this disease, it was not "getting in an accident" versus getting this disease.

      Yes. Getting in an accident is deadlier than getting this disease. But most drivers don't get into accidents during the year.

      There are nearly 200 million licensed drivers in the US -- so the odds of getting in an accident because of driving are 2.7%, and the odds of going all the way to a fatal accident just because of driving are 0.0164% (1 death per 6,000 drivers per year). The odds of this disease killing you is 0.2% (1 death per 500 diagnosed per year).

      Just because fewer total people in the US die of this disease per year than die of driving does *not* make the disease safer.

      Parent is not missing a step. You missed that the suggestion provided was that *driving* is deadlier than getting this disease; and wrongly inferred that the number of accidents is a useful substitute for the number of drivers.

      Oh, and if your use of statistics leads you to three different conclusions (7 times, 3 times, and 37 times), then you are probably using statistics wrong.

    14. Re:infects 50 million, eh? by Anonymous Coward · · Score: 0

      Math is easy, definition and interpretation is the hard part. Let me give you a nice primer on the subject. Might I also suggest understanding logic in natural language, an equally difficult subject few bother to get even an elementary education in.

    15. Re:infects 50 million, eh? by Gr8Apes · · Score: 1

      Oh and I forgot, at least one treatment for it, Flagyl, actually makes you feel worse. But at least then you're done and can stop taking it.

      As a bonus, while you're on Flagyl you can't even drink to forget your problems.

      That's ok, you won't want to, as you'll be too busy moaning that you're dying already, provided it doesn't kill you. That is one of the "side effects" not listed there but was on the bottle I saw that you should immediately contact your physician for...

      --
      The cesspool just got a check and balance.
    16. Re:infects 50 million, eh? by mr.mctibbs · · Score: 1

      I was trying to figure out what's wrong with you, but I'll just assume you're drunk.

  5. Looks like a pretty low death rate. by Anonymous Coward · · Score: 0

    100,000 deaths per year over 50 million total infected = 0.2% mortality rate per year. I'd take those odds.

    1. Re:Looks like a pretty low death rate. by symes · · Score: 1

      If you risk infection in the course of activities you have to undertake, like driving to work, then fine. But I for one would not choose to subject my self to a risk of .2% through infection by this flesh munching turd monster. And if infected I would rather take a course of pills to erradicate it from my body, even if there were transient side effects such as explosive diarrhea.

  6. How? by Tablizer · · Score: 1

    a new report reveals how the microbe does its deadly damage: by eating cells alive, piece by piece.

    This is unique? How else do microbes make a living? Amway sales?

    --
    Table-ized A.I.
    1. Re:How? by rubycodez · · Score: 1

      many merely coexist with you, eating nutrients carried about by your precious fluids.

    2. Re:How? by hawkeyeMI · · Score: 1

      Not me, I drink only the purest rainwater to protect my bodily fluids.

      --
      Error 404 - Sig Not Found
  7. Re:The reason the Republicans are fighting against by dugancent · · Score: 1

    He isn't a leftist, he's a troll.

    --
    SJWs are the new boogeyman. -Me
  8. Re:The reason the Republicans are fighting against by TheGratefulNet · · Score: 1, Offtopic

    how absurd.

    the poor and 'non whites' are the ones who mow the lawns, clean the houses, cook their food, change their oil, etc.

    they NEED a sub-class around to SERVE them. the sub-class dying out is a nightmare to the ultra rich.

    --

    --
    "It is now safe to switch off your computer."
  9. Wonder what's worse? by Anonymous Coward · · Score: 0

    This amoeba or that brain-eating amoeba.

    1. Re:Wonder what's worse? by Opportunist · · Score: 3, Funny

      That's like asking what's worse, Parkinson or Alzheimer. Does it really matter whether you spill your beer or whether you forgot where you put it?

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
  10. What's eating you? by MindPrison · · Score: 3, Funny

    Ah, perfect - now I have an answer for that annoying question people sometimes ask me:

    What's eating you?

    E. histolytica!

    --
    What this world is coming to - is for you and me to decide.
  11. O_O by Anonymous Coward · · Score: 0

    Are you sure this is not my EX doing this?

  12. not anymore by dutchwhizzman · · Score: 2

    Malaria and dengue are on the rise again. Humans have created so many opportunities in their own landfills and housing (a single old car tire is enough) that these mosquitoes dont go away if you drain a swamp. We are also rather good at helping these animals spread, since every continent not Antarctica now has both species carrying the disease roaming in the wild because we let them ride along with our goods. As far as killing them goes, they have proven to be able to mutate such that common `environmentally friendly pesticides no longer work and we have to resort to really nasty stuff to sufficiently kill an outbreak. So, statistically, you dont treat malaria or dengue but you try to avoid it, contain the spread and fight the symptoms if you happen to get ill from it.

    --
    I was promised a flying car. Where is my flying car?
  13. Okay this bit made me laugh! by Anonymous Coward · · Score: 0

    says infectious disease specialist William Petri ...
    Excuse me Petri pass be the petri.
    When he was younger was he a bit of a dish?
    Is he a relation http://en.wikipedia.org/wiki/Julius_Richard_Petri ?

  14. Eats Human Intestines, Cell By Cell by korbulon · · Score: 1

    In other words the parasite equivalent of Taco Bell.

  15. Re:The reason the Republicans are fighting against by SuricouRaven · · Score: 1

    Besides, how can you know you are rich if you don't have some poor people for comparison?

  16. Eating fat by Tekoneiric · · Score: 3, Interesting

    Why is there never a parasite that eats unwanted fat and sugars then poops useful enzymes and vitamins into it's host's body?

    --
    *It's not what you can do for the Dark Side but what the Dark Side can do for you!*
    1. Re:Eating fat by Anonymous Coward · · Score: 0

      Our bodies already do that. The problem is people keep adding more unwanted fat and sugars.

    2. Re:Eating fat by Anonymous Coward · · Score: 0

      There is, its called a human

  17. Fair's fair... by Anonymous Coward · · Score: 0

    ...after all, we eat it, and millions of other life forms.

    In fact, humans aren't a basic life-form at all. Each one is a collection of millions of smaller life-forms which have banded together to improve their collective chances. Inside us, there are lots of cells being 'eaten alive', regenerated, dying and being re-absorbed, you name it.

    A description of our normal digestive processes would seem appalling to a plant. After all, we tear their living cells apart and plunge them into a bath of acid and chemicals to disintegrate them....

  18. One thing to look out for by Maxo-Texas · · Score: 1

    Some human strains may have adapted to this and need it to be healthy.

    We already have a similar adaption to worm parasites and without a worm infection those people suffer until they get one.

    --
    She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
  19. Re:The reason the Republicans are fighting against by Opportunist · · Score: 1

    You nuts? If all the serfs die out, you'd have to WORK again!

    --
    We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
  20. The only question that remains by Opportunist · · Score: 1

    Did they manage to infect Madagascar and Greenland?

    --
    We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
    1. Re:The only question that remains by Anonymous Coward · · Score: 0

      No, they closed their ports and airpots too soon.

  21. I'm guessing... by Anonymous Coward · · Score: 0

    ...that you haven't been in a multiple pile-up, had part of a car body slice through your stomach, both legs broken and your skull fractured.

    The point of the OP is that that is MORE likely to happen to you than death from dysentery....

    1. Re:I'm guessing... by hawkeyeMI · · Score: 1

      And my point is that there are things worse than a higher risk of death.

      --
      Error 404 - Sig Not Found
  22. What's eating Gilbert Grape? by iced_tea · · Score: 1

    Entamoeba histolytica!

  23. Yes by Anonymous Coward · · Score: 0

    THere is, but it's not called a parasite. Parasites are creatures that harm their host. What you are looking for are mutualistic bacteria.

  24. Seriously? by sirwired · · Score: 1

    Often, the tests for intestinal parasites (usually from a series of stool samples) don't actually work. While false positives are rare, false negatives are quite common.

    Given that cancer is usually an actual tumor (or, at the least, something that is blindingly obvious on a microscope slide), the odds of getting treated for cancer when you really had a parasite is pretty much zero.

    And likewise, the flu has pretty distinctive symptoms (and a somewhat reliable test) that you are unlikely to be treated for influenza but be suffering from a parasite.

    A mandatory test for any given parasite would be a fantastically expensive waste of money for relatively little benefit. And of course there are a crazy number of parasites it's possible to infect a human with; which ones do you test for?

  25. fascinating organism by Anonymous Coward · · Score: 0

    Maybe they can modify it to only eat stomach cancer.