Talk:Chagas disease

From Wikipedia, the free encyclopedia

Featured article star Chagas disease is a featured article; it (or a previous version of it) has been identified as one of the best articles produced by the Wikipedia community. Even so, if you can update or improve it, please do.
Main Page trophy This article appeared on Wikipedia's Main Page as Today's featured article on July 31, 2005.
July 8, 2005 Featured article candidate Promoted
WikiProject Medicine This article is within the scope of WikiProject Medicine. Please visit the project page for details or ask questions at the doctor's mess.
Featured article FA This page has been rated as FA-Class on the quality assessment scale
Mid This article has been rated as Mid-importance on the importance assessment scale
Peer review This Natsci article has been selected for Version 0.5 and subsequent release versions of Wikipedia. It has been rated FA-Class on the assessment scale (comments).
This article was selected on the Medicine portal as one of Wikipedia's best articles related to Medicine.
Flag
Portal
 Chagas disease is within the scope of WikiProject Brazil, which aims to improve Wikipedia's coverage of Brazil and Brazil-related topics. If you would like to participate, visit the project page.
Featured article FA This article has been rated as FA-class on the quality scale.
High This article has been rated as high-importance on the importance scale.
To-do list for Brazil:

Contents

[edit] older entries

Hello, contradiction in the main article : "Nevertheless, he at least believed falsely until 1925, that the main infection route is by the bite of the insect and not by the feces" ... actualy is seems that's it's mainly the bug!! Otherwise it would be good to push the details a bit more!

  • -: I corrected: Nevertheless, he at least believed falsely until 1925, that the main infection route is by the bite of the insect - and not by its feces, as this was proposed by his colleague Emile Brumpt 1915 and assured by Silveira Dias 1932, Cardoso 1938 and Brumpt himself 1939. Good english now?

Again : "ore rarely, better constructed houses may harbor the insect vector, due to the use of rough materials for making roofs, such as bamboo and thatch"

I would say due to the use of plaster or vinyl, difficult for a x millimeter black pest to hide on white plaster roof, but in bamboos!!!!!!!!!!!!! Let's be serious here !!! Could somody better knoledgable on that topic, make the necessary corrections!!

  • i dont understand this question.--



Hello, don't want to slap my own biases on what is a very nice wikipaedia entry but thought it worth mentioning that the answers to a lot of the questions raised here as well as a lot more detail on this disease and the organism that causes it are found in this recent book on the subject.

http://www.amazon.com/gp/product/1402073232/104-5157415-3057545

"solation of the agent by: a) inoculation into mice; b) culture in specialized media (e.g. NNN, LIT); and c) xenodiagnosis, where uninfected reduviidae bugs are fed on the patient's blood, and their gut contents examined for parasites 4 weeks later."

mistake?: i read in the german Dönges/Thieme it is only TWO weeks, it is 4 weeks with mice and guinea pig, only m.03/05

[edit] Some details

Hi. I liked the article, especially since I had not thought that we had such an extensive material on Chagas disease. I just have two points, one is a personal curiosity of mine, the second is really a suggestion that may be included in the article.
1) My question is (and maybe the article could be more emphatic about it): is there a cure for Chagas disease? I remember studying it at school, and books, if I recall correctly, used to say that it was incurable. Maybe this has changed? Or does it remain as a chronic disease, with the patient having to be treated for symptoms for the rest of his life?
2) About the recent outbreak in Santa Catarina, maybe the article could state that over 50 thousand people, spreading across 4 states (tourists that were visiting the Santa Catarina coast) are expected to get tested for the disease. But more importantly, maybe we should say something about this theory of the scientists over there: they say that deaths have occurred because the infection by the pathogen was much, much more accute than normal. Usually, the T.C. enters the host through the bite wound, when the person scratches the site (a detail that should be in the article also), and thus it does so in a very small quantity. In the case of the sugar cane infection, however, the "victims" ingested an unusually large quantity of the pathogen, which theoretically sped the cycle of the disease considerably, leading to death in some cases (which would not occur in such a short period since infection).
I have not edited the article myself because I am not knowlegeable enough in this field to edit this type of work. I'd end up messing things up and misinforming the reader. But I tought that the suggestions were good. Regards, Redux 14:24, 26 Mar 2005 (UTC)

Hello, Redux, I wrote most of the article, including the news about the new type of infection. I studied medicine at the School of Medicine of Ribeirão Preto, Brazil, recognized as the center of excellence in research on Chagas disease, and Fritz Köberle, one of the most famous researchers on the etiology of Chagas disease. Responding to your questions: yes, the disease is incurable in the chronic phase, and it is debatable whether it can be cured in the acute phase. A vaccine was developed in Ribeirão Preto but it was found economically unfeasible. I will add the information about scratching, you are correct (note that I have added a picture about the chagoma), and regarding the new outbreak in Santa Catarina, I am waiting for more news to supplement it. The hypothesis about the higher severity due to oral ingestion you have commented is correct, but it is still a hypothesis. It could be a new strain, too. User:Rsabbatini.
Hi Rsabbatini. Thank you for your answers. I had indeed noticed that you are the main contributor to this article. I take this opportunity to congratulate you on it, it's quite good. I've seen your latest additions, and they work very well at addressing the suggestions I had made. Your answer has triggered another doubt in me though. So, if I may abuse your good will: so there actually is a working vaccine that nobody gets because it's too expensive?? That's a terrible thing, unless the vaccine wasn't effective, or maybe it was hazardous in some way? Also, if I may ask (although I'm not sure wheather this would have a place in the article): suppose you live in a risk area (for the insect vector), if you notice a wound that may be a chagoma, resist the urge to scratch and brush the area with alcohol (or maybe just wash it), would that be effective in preventing the pathogen from entering the body? Or maybe as you clean the area (with alcohol or water) you might end up pushing the pathogen in just the same? As you probably noticed, I'm Brazilian too, and I remember clearly studying Chagas disease at school and thinking what would I do if I ever saw a chagoma in my skin (I was very young then, and I spent a month checking every mosquito bite before scratching, to make sure that it wasn't a chagoma. I was scared by the notion of this incurable disease that could be transmited by an insect bite. But of course, I don't live in a risk area for the Barbeiro). Regards, Redux 02:11, 28 Mar 2005 (UTC)
Nice to know that you are a Brazilian, too. We are very few here. Theoretically you are right, if we refrain to scratch and desinfect the area the blood infection should not occur. However, this happens unconsciously at night, so, unless you don't sleep... The first week I slept at the Moradia dos Estudantes in the Medical School, we discovered a barbeiro. Most astonishing the dividing walls of the moradia were compressed sugar cane straw!!! (unbelievable, in the medical school were Chagas was so studied). I got in a panic and he had the barbeiro tested, but fortunately it was clean. The students protested and the straw bricks were layered over with mortar. But or a few months everyone slept with a mosquito net! Regarding the vaccine: 1) it did not protect 100% (only about 85%), and it could not be obtained in large animals, such as horses, which produce a large amount of antiserum. My professor, Dr. Becker, infected himself and his lab assistant, Helinho, with Chagas (very corageously or silly, it depends) after vaccination and it worked. Furthermore, spending money in prevention would be more useful, because vaccinating everybody was also found to be too difficult .
Unbelievable this story! Talk about irony! But that makes me think that the Barbeiro appears to have a sore spot for sugar cane, which would be a hazardous substance unless closely controled by sanitation authorities. Maybe this would be worth including in the article? Although there's this new stuff coming from Pará, about a smaller-scale outbreak that has apparently been brought on by contaminated Açaí. In the "Santa Catarina front", they are now saying that there's a possibility that a Barbeiro bug (the actual insect) might have been grinded along with the sugar cane (argh!). I don't know if that would be worth including though. Also, your story made me realize that the article is not all that clear in the fact that not all the vector insects carry the pathogen (as per the one you found in the school dorm, which was clean). That may appear obvious, but many people tend to think that all of the vector bugs (such as the Barbeiro) carry the T.C. within then, which is not the case. Regards, Redux 13:47, 1 Apr 2005 (UTC)

RSabattini, is it possible, for the sake of completeness of this article, to provide a reference or a link on the paper that reports the oral infection trials held by Instituto Oswaldo Cruz?

I tried to find, but it seems that they stil remain unpublished. I got this second-hand from a science news source in Brazil. User:Rsabbatini 2 July 2005

RSabbatini: A quibble - I live in Florianópolis, SC, and here, we call sugarcane juice "caldo de cana". Just in case any vacationing gringos are reading this and want to know what to avoid!

Good suggestion. I produced too the article on garapa and will add this regional term. User:Rsabbatini 2 July 2005

—== ideas ==

I've done some editing of the article in the past day or so. It looks really good, but there are a few things that need to be fixed that I probably can't do on my own:

  • Sources: inline references (like footnotes) should be added for a lot of the claims, for instance "Chagas’ work is unique in the history of medicine..." I can set up the footnoting system if the author can identify sources for the various claims. As an example, take a look at Myxobolus cerebralis, which I helped write.
  • *In the last paragraph of "epidemiology and geographical distribution," could we add more information about the insects' "domestic behavior?" Right now, it's a little unclear. This one is fixed now, but the others (especially the map) still need to be fixed. Dave (talk) July 7, 2005 18:21 (UTC)
  • Can someon update the map to reflect its range in the U.S.?
  • Clarify chagoma in the "clinical manifestations" section. I'm not sure how to interpret " A local lesion (so called chagoma (see picture), palpebral edema)." Could it be rewritten to say "a local lesion, called a chagoma, forms due to palpebral edema? I'm not sure I understand the relationship between lesions, edema, and chagoma.
    • The issue was a bit unclear. The way I've understood it, a chagoma is a nodule at the site of inoculation, while the palpebral edema seen in the picture is actually Romaña's sign, a swelling of the eyebrow after inoculation at the conjunctiva. Zyryab 22:22, 14 February 2006 (UTC)

I hope we can get this featured. I'm always very impressed when people can do something like this in a foreign language because I know I'd never be able to even come close.

Best of luck, Dave (talk) July 5, 2005 20:39 (UTC) /* ideas */ How about some photos of bites. I imagine a lot of people who check this site are paranoid about a suspicious bite (like me), and could do with some on the spot info as to how to differentiate between different bites. For instance I spent a few days in thatched huts in the Amazon in Bolivia, and a few days later noticed a mosquito bite sized hard lump on my head, within the hairline. It stung strongly and sporadically for a few dyas, but responded well to standard insect bite cream. Is now small but has developed violet colour. Should I be worried?

Leslie Beben chiming in - Chagas' cardiomyopathy probably represents a "gold standard" in appreciation of a singularly lethal swath of autonomic devastation cut through the myocardium (or esophagus, colon, etc. under vagal control) initially dealt to an unfortunate host by a common household insect. Chagas' cardiomyopathy likely represents cardiac autonomic insufficiency in a very specific form as the sinoatrial tree and spinal ganglia are usually spared. Chagas' helps us to see that there are two electrical supply systems to the heart. First order electrical control of the myocardium is governed by traditionally understood mechanisms of sinoatrial propagation. Second order control is derived from background autonomic control derived from the vagus nerve and spinal accessory nerves and ganglia. Chagas' shows an etiology specific dismantling of vagal/autonomic control that inevitably leads to geometric derangement and subsequently clinically observable diastolic dysfunction.

[edit] double see http://en.wikipedia.org/wiki/Chagas_disease#Alternative_infection_mechanism

Recent Outbreaks

In March, 2005, in Santa Catarina, Brazil, at least 19 people got the disease by ingesting sugar cane juice that was pressed together with some bugs. It was a very strange case and Brazilian Health Vigilance demonstrated a special interest to solve the origin of infection. At least 3, from the 19 accounted for, people died. Folha On-line news (in Portuguese)

[edit] Version 0.5 nomination failed

This article is considered to fall outside the scope of the Version 0.5 test release, since this version only includes a limited number of articles. It is now held ready for a later version such as Version 1.0 nomination. Walkerma 03:58, 5 June 2006 (UTC)

Just added the results from an article that came out this week about chagas in NEJM. Sorry about the untabled version... Just learned how to do tables as well.Jfmarchini 00:48, 29 August 2006 (UTC)

[edit] Pneumocystis & Schizotrypanum

I added in links to Chagas' discovery of Pneumocystis and its complicating factor in the description of Schizotrypanum as an independent genus based upon two mixed life-cycles. I also added a link to the the original validating description of Trypanosoma cruzi earlier than the description of Schizotrypanum cruzi. These details are explained in the reference by Redhead, Cushion, Frenkel & Stringer 2006. Chagas actually illustrated Pneumocystis in the latter 1909 paper on Schizotrypanum. He differentiated both pathogens in 1912. Heliocybe 13:24, 3 April 2007 (UTC)

[edit] Image

Can someone please fix the broken image in the article? -- Permafrost 01:19, 12 June 2007 (UTC)

Strange. It was deleted locally as being available on Commons, but now the file is gone from Commons (only the image description page is left). Fvasconcellos (t·c) 01:40, 12 June 2007 (UTC)

Which image was this? I can't see any missing. TimVickers 02:42, 12 June 2007 (UTC)

See Wikipedia:Administrators' noticeboard#Image undeletion. It's been restored. Fvasconcellos (t·c) 09:22, 12 June 2007 (UTC)

[edit] Name

I think the name is "Chagas' disease" rather than "Chagas disease". I've added the apostrophe to the text, hope I haven't missed any. Tim Vickers 17:53, 11 July 2007 (UTC)

[edit] Life cycle Image

Can some one re-draw this CDC image pls? It looks too big and odd yet barely readable--Countincr ( T@lk ) 00:26, 12 July 2007 (UTC)

[edit] Blood transfusion and monitoring

JAMA last week has come up with a strategy how to monitor people who have been found to be Chagas serology positive in screening of blood donations. JFW | T@lk 06:45, 20 November 2007 (UTC)