Talk:Infectious disease/Archive 1

I'm
I'm not sure why "Therapy" was replaced by "Treatment" (User:Alex.tan). I think antimicrobial therapy is wholly allright. JFW 19:58, 1 Apr 2004 (UTC)

Agents and Vectors
The example about Plasmodium falciparum is incorrect. The parasite can be acquired from blood transfusion. It also misuses the term vector. There are two types, biological and mechanical. A biological vector retains the microbe inside itself, such as a Reduviid bug carrying T. cruzi metacyclic trypomastigotes, while a mechanical vector is like a housefly, which lands on feces, picks up bacteria on its body, and subsequently lands on someones food, delivering the bacteria to the food. A respiratory droplet is just that. If it lands on an inanimate object, then the object becomes a fomite, which is an object that carries an infectious agent, but neither the droplet nor the fomite is a vector. A vector is an animate transmitter of disease.

As there has beeen no response to this, I will go ahead and rewrite the section. --eukaryotica 03:21, 9 January 2007 (UTC)

AIDS
Is it possible to die from AIDS? I thought AIDS had never killed a single person? Surely the data corrisponds with indirect deaths. Should that be mentioned in the article? mastodon 01:36, 6 November 2005 (UTC)
 * To the same extent that people descending from a tall building do not die of falling. Midgley 15:28, 7 February 2006 (UTC)

Yeah. That's absurd. No one directly dies of any of these. Heart failure could be listed for almost every death. Not really interesting. —Preceding unsigned comment added by 70.128.93.238 (talk) 17:17, 11 March 2010 (UTC)

New section
could use some sources --DocJohnny 12:51, 2 January 2006 (UTC)

Terminology
It is truly hideous that this article doesnt use the neccessary terms. There are two main factos to an infectious disease, its potency in the host, and its potential to spread. I can at this moment remember neither of these terms, which is why I came to this article, and was astonished not to find it in the first paragraph. Terrible, truly terrible. —Preceding unsigned comment added by 89.100.214.237 (talk) 07:53, 14 May 2009 (UTC)

Public health, vaccination and isolation. Control of vectors.
How we fight disease includes those and they should at least be linked here. Midgley 15:27, 7 February 2006 (UTC)

Non-communicable disease
I've created Non-communicable disease as a stub - mentioning it so it can be linked where appropriate by those focusing on this area, and in case there's an article on the same topic, under a different name (in which case, feel free to merge it). --Singkong2005 talk 11:59, 31 August 2006 (UTC)

Extra words in first section
I'd like to suggest these extra words, bearing in mind that Wikipedia is a popular as well as a technical resource. I realise they are implied by the first paragraph, but they might nevertheless help more people to understand things rationally, especially given the popular and press hysteria on health topics. I am prompted by this well-meaning change. While the word "infectious" can cause alarm, it is simply a term for a whole class of diseases. Infectious diseases need not be dangerous, and can't may not spread from person to person at all. Or something to that effect, but avoiding any technical words. Any thoughts?

Also, contagious disease redirects here. Is it really a synomym? The dictionary definition suggests it is a disease which can be transmitted person to person. Notinasnaid 07:36, 10 October 2006 (UTC)


 * I really think the new sentence is bad. It presupposes that people find infections scary. Do they? How will you prove that? JFW | T@lk  21:46, 28 October 2006 (UTC)
 * The obvious way to prove it is to find a source. This should be done, but I don't feel that this particular sentence stands out above all the others as needing sources first. But now I've got a reply at last, how about the issue of the redirect of "contagious"?

Notinasnaid 08:33, 29 October 2006 (UTC)
 * By the way, in this area (which I am trying to make clearer to the lay visitor to this page), perhaps someone can help me understand it. Take a look at this link on the BBC web site, describing a science book. Is the reporter misusing "infectious disease" in "By doing that we were able to see that it was characteristically a disease spread person to person, it was an infectious disease." Do they mean "communicable Disease" or "contagious disease" or are these synonyms? Notinasnaid 09:27, 29 October 2006 (UTC)

External link
I added a link to Journal Watch's ID site, but it was removed as a "spam link." This seems pretty rigid, considering its focus is medical journal articles on infectious diseases. This is spam, while a "blog" (actually, a blog placeholder) is not? Erikd7 15:16, 12 October 2006 (UTC)
 * Thanks for pointing the blog out. Wikipedia doesn't link to blogs, so I've removed it. I have no knowledge of the other link you mention: I'd recommend you post a proposed link and description here. Anyone commenting should reviewing External links for the closest thing we have to policy. Notinasnaid 15:21, 12 October 2006 (UTC)

As a matter of technicality: Communicable: Spread via person to person. Contagious: EASILY spread via person to person. EX: Gonorrhea is communicable but not contagious. EX: Influenza is communicable and contagious. —Preceding unsigned comment added by 199.17.205.3 (talk) 20:13, 27 October 2008 (UTC)

I also added a link to an encyclopedic journal containing articles relevant to the treatment of infectious disease, and it was also removed as "spam". Can anyone tell me why this is? Nanomedicine (talk) 13:45, 23 June 2009 (UTC)

The Introduction
I have rewritten the introduction and will return at a later date to clean up the rest. While this is an admirable attempt to address communicable disease, the use of terms such as "replicator" and the erronious definition of communicable indicate that the principle author is unfamiliar with the discipline. The definition of contagion or communicable is clearly set out in many online dictionaries, including Dorland's medical dictionary and should be referred to, rather than an innate understanding of the term. Definitional differences are sometimes apparent in that some authors define communicable as only being passed from person to person, but generally host to person avoids the trouble of having to consider one essential illness as two, as for example bubonic plague (flea to person), as different from pneumonic plague (person to person) even though the bacterium, Yersinia pestis, and the cause of death, septic shock, are the same. Likewise malaria is transmitted person to person via a mosquito.--eukaryotica 19:35, 24 November 2006 (UTC)


 * While I agree that the prior introduction needs work (and the article as a whole), I don't think that the definition that you added tells the entire story either. It also lacks some of the critical elements required by the Manual of Style, and contained no actual references to any medical definition. In addition, there is not such thing as a "principle author" on any Wikipedia article, all helpful contributions are welcomed.


 * I have replaced the new definition with one that is more applicable and clearly differentiates between infectious and contagious disease. Cheers--DO11.10 22:44, 24 November 2006 (UTC)

Your interesting comments are appreciated and welcomed. While it may be that no one takes resposibility for any complete section, I would have to assume that the person who wrote what I replaced is the principle author of that writing. He and I both suffered from the stylistic errors you refer to and when I rewrite what you have offered, I will be sure to make it fit the Wiki style sheet. But you are correct, I am guessing that the person who wrote "replicator" is also the person who wrote the definition I replaced, and I may very well be mistaken in that. I cannot see how you would not consider yourself as the principle author of the section you submitted, as I am certain you would be rightly proud to take credit for such an improvement as you have put forward.

While differentiation between infectious and communicable disease would be a welcome addition, the citation you give in a link to the Washington State site does not differentiate between communicable disease and infectious disease, rather it equates them, and is an example of the variation in definition one can find among various authors. Your link states


 * "An illness due to a specific infectious agent or its toxic products that arises through transmission of that agent or its products from an infected person, animal or inanimate reservoir to a susceptible host; either directly or indirectly through an intermediate plant or animal host, vector or the inanimate environment (synonym: infectious disease)."

I disagree, as I presume you do too, although you cited this source, that a disease picked up by traumatic contact with an inanimate object is communicable. Such a notion undercuts the necessity of communicating an essential element of contagion - that an infectious agent amplifies itself in a population by spread from one person to another.

I would suggest that medical texts or texts in medical or general microbiology be used as a source for an acceptable definition of communicable. Here are a few:

Sherris Medical Microbiology 4th edition:

"Communicable infections require that an organism be able to leave the body in a form that is directly infectious or is able to become so after development in a suitable environment."

Sherris offers three categories of non-communicable infections which he defines as infections that are not passed from human to human: infections from normal flora, infections from preformed toxins, and infections from environmental organisms (such as my tetanus example).

Warren Levinson in his USMLE board review text Medical Microbiology and Immunology, seventh edition states

"Many, but not all, infections are communicable, ie, are spread from host to host. For example, tuberculosis is communicable, that is, it is spread from person to person via airborne droplets produced by coughing; but botulism is not because the exotoxin produced by the organism in the contaminated food affects only those eating that food.  If a disease is highly communicable, the term "contagious" is applied. "

Here Dr. Levinson does not categorically state that normal flora nor non-intoxicating diseases such as peritonitis or Clostridial enterocolitis secondary to antibiotic treatment are not communicable, and indeed some hospitals go to extreme measures to suppress C. difficile even though it is resident in the intestinal tract. This is because in the long run, they are communicable, since the sterile newborn begins to acquire its normal flora by contact with people. And in the long run, some of those normal flora may become pathogenic. But this is splitting hairs. Communicable is supposed to mean something specific. I believe Dr. Levinson's intent is to circumscribe the term contagious with the larger circle of "communicable" rather than equate them, as Dorlands does (see previous comment).

Insofar as infection goes, in the wonderfully detailed text by Madigan and Martinko, Brock The Biology of Microorganisms, eleventh edition, they state that

"Infection refers to any situation in which a microorganism is established and growing in a host, whether or not the host is harmed."

And disease to them is the common definition - "damage or injury to the host that impairs host function."

Infectious disease falls out from this, wouldn't you agree? You may wish to tighten up the wording of your definition a bit, or if you wish, I will.

I would tend to agree with Brock, that infection is establishment of growth or at least stasis within a host, and that intoxications such as those represented by heat stable enterotoxins contributed by a dead pathogen do not qualify as infections, but are intoxications unless they represent actively growing organisms.

Insofar as the definition of communicable disease goes, I would stick with Dorland's definition of communicable:

"capable of being transmitted from one person or species to another, as a communicable disease; contagious"

http://www.mercksource.com/pp/us/cns/cns_hl_dorlands.jspzQzpgzEzzSzppdocszSzuszSzcommonzSzdorlandszSzdorlandzSzdmd_c_49zPzhtm

It is unambiguous and largely leaves out the possibility of including opportunistic infections, intoxictions or environmental injuries, even though those pathogens may very well have passed through some other host in their ancestry.

I returned to this page to spend some time with the text, however this was time better spent, since I was able to consider the breadth of this definition. Should you wish, I will come back from time to time and carry out a conversation on this very important subject. --eukaryotica 21:22, 25 November 2006 (UTC)

So I would offer this:

Infectious disease arises as a result of the establishment or growth of a microorganism within a host which so damages or injures the host as to impair host function. Infectious diseases may be communicable or non-communicable. A communicable disease is transmitted from one person or species to another, while a non-communicable disease is the result of an intoxication or abnormal colonization by an organism that would not result in a similar disease given contact between the patient and a healthy person. Contagious is a term that may be used either synonomously with communicable, or to describe a more virulent, readily transmissible form of a communicable disease. --eukaryotica 23:10, 25 November 2006 (UTC)


 * I am pretty sure I understood your concerns, and have modified the intro to reflect these, but I may have missed something. The Washington ref was actually for the terms infectivity and infectiousness, not the contagious part (I think that is more clear now).


 * I guess that the problem I have with your definitions is that they seem to be written to communicate an idea to persons whom already understand the subject. While Wikipedia articles should be written with the intention of familiarizing the reader with a concept that they might not fully understand. I am a scientist (although not a microbiologist, as I would imagine you are) and to be honest I am not really sure what intoxicating diseases are? I could guess, but I don't think that is what you really want.

I would be quite comfortable working with you on this article. Please let me know that you think? Also, feel free to contact me by way of my talk page.--DO11.10 04:25, 26 November 2006 (UTC)

Yes, it is likely I am too close to the subject to communicate it effectively to a wider audience, however we both use the internal jargon to some extent, such as "pathways". I think I would like to go over this carefully, if you don't mind, since I often turn to Wikipedia for reminders and they often have scholarly treatments of difficult subjects mixed in with familiar treatments such as we have begun to rework. I think "infectious disease" should get a thorough inspection, since many people from every level of understanding will come to Wiki for definitive treatment. Classes resume for me tomorrow and I will not be able to work on this consistently until mid December when I have completed grading. (Yes, I teach microbiology.)

So for a beginning, lets look at the first sentence.

An infectious disease is a clinically evident disease of humans or animals that damages or injures the host so as to impair host function, and results from the presence and activity of a pathogenic microbial agent, including viruses, bacteria, fungi, protozoa, multicellular parasites, and aberrant proteins known as prions.

The term "disease" is used twice, but so long as it is linked the definition reveals itself as a category of the subsuming term "disease". Genetic disease, psychological disease, social disease and so on might be other categories. It sounds a bit awkward though. "Illness"?

I am not certain that clinical evidence is necessary for a disease to be infectious. Many infectious diseases are spread without a person being aware of it. For example, blood screening catches subclinical HIV, Hepatitis and arbovirus infections while there is no clinical evidence of disease. While there is laboratory evidence, such as antibody reactivity in the ELISA screening, the term "clinical evidence" implies active illness that is obvious and would drive a patient to a doctors office, or put them in bed. So to include "clinically evident" interprets infectious disease as only disease passed from one apparently ill person to a new host and would exclude the acquisition of a disease from a carrier. In this case, illnesses produced by Human Herpesvirus I and HHV II, which are notorious for spread from carriers, would not be considered infectious diseases, nor would other subclinical illnesses that only become clinically evident at certain times during an infection, such as Human papillomavirus, subclinical gonorrhoea, HIV disease, syphillis and a few other STD's, as well as typhoid from a biliary carrier, E. coli O157:H7 from healthy cattle or variant CJD from an organ donor yielding a corneal transplant. I think the examples are numerous enough to exclude the term "clinically" at least from the definition. What do you think?

The term "pathogenic" seems a little circular and this is dangerous I think, because it means that a term is fully defined without reference to anything outside of its definition. I think a pathogenic agent is defined as a pathogen if it can cause disease. Terming a disease causing microbe a pathogenic agent implies that non-pathogenic agents cannot cause disease, but this is not true. Many gut bacteria can cause fatal illnesses if released into the bloodstream, yet are not commonly thought of as pathogens, but rather as beneficial and normal flora. However I think this might be corrected if the term "pathogen" were taken from its adjectival position and moved into a prepositional pharse, something like "...of a microbial agent that could be considered a pathogen" or "of a microbial agent capable of pathogenicity", or just leaving it out.

Within this same sentence, there are two other things that come to mind. First, "presence and activity". Most authors think that colonization, meaning growth, is necessary for a disease to progress. Mere presence might imply that dead bacteria could cause disease. This is an interesting point. Injection of LPS by itself can bring on Gram negative shock, and thus one might presume that someone who came in contact with a blood borne load of LPS, such as in improperly sterile filtered saline, would suffer from an infectious disease. I don't know. It is interesting. I think that one possibility is that the recipient would not be able to propagate the same illness, but meeting Koch's postulates is not necessary to consider, for example, West Nile an infectious illness, since people get that from birds via mosquitoes. So here I am a bit stumped. The popular concept is that an infectious illness comes from colonization (ie growth) and/or intoxication. You say "presence". That would suggest that you are on the edge of accepting a mere intoxication as an infectious illness. Levinson does not. It also verges on defining poisonings of any sort as infectious. And in dead end illnesses such as West Nile where humans are accidental hosts, they are still capable of transmitting it under unusual cirmstances. Many blood borne diseases can be transmitted via transfusion. I think an infectious disease must be "propagatable", if that is a word. It denotes something that can increase in number, although not necessarily. So I would favor changing "presence" to something that denotes growth, propagation or increase. A more standard approach to "presence and activity" would be to use the mechanistic descriptions of "colonization, invasion, and/or intoxication", and further elaborate later on what an intoxicant might be, or perhaps use the term "poisoning" or enumerate the possible intoxicants by categories such as A/B toxins, or neurotoxins and so on. mmm, so, in answer to your question, it seems clear that infectious dieases are not poisonings per se, but can result in poisonings. The infection must come with, and be the source of, the poisoning. Yet I am still a little uncomfortable, since I can imagine someone acquiring an infectious dose of an organism that does not propagate, yet delivers sufficient intoxicant to cause disease. Vibrio cholerae may sometimes work like that, although it normally propagates and colonizes. Staphylococcal food poisoning is another, from the hands of one person, into the potato salad, and killed off by stomach acid, yet delivering sufficient toxin to cause disease. According to Levinson, these are not communicable. But are they infectious? I suppose it comes down to propagation. Is serial passage necessary and sufficient to consider a disease infections? An accidental host grows the agent, but does not normally propagate it by passage to another host. Serial passage would seem not to be necessary, though certainly it is sufficient. What is necessary for something to be considered infectious? Presence or growth? And what are we talking about? Microbes or intoxicants?

Also, a minor point, there is a syntactical agreement problem with your enumeration of infectious agents. I suggest pluralizing "agent". Since we are not dealing with plants, I agree with the enumeration. It is not perfectly comprehensive since there is at least one instance I have come across of Archeal (semi)-pathogenicity (methanogenic flatulence), and an instance of an alga that can cause a cutaneous infection. And it leaves open the possibility that other agents that might not be presently known as infectious agents of animals, such as viroids or other forms of naked nucleic acids.

I must return to my lectures now, but I will return to this page sometime during the coming week to receive your thoughts on my peripatetic musings. --eukaryotica 19:43, 26 November 2006 (UTC)


 * I have added several new peices to the article, I hope that you agree with my edits, if not please feel free to edit them. In addition, I thought I would mention a paper I came across that you might find interesting Host-Pathogen Interactions: Basic Concepts of Microbial Commensalism, Colonization, Infection, and Disease. Also, while I thank you for signing your posts, would you mind using the "signature button"-(the one with the squiggly line) on the edit bar above or, by typing four tildes like this: ~ this makes a link to your talk page so that other users can contact you, and inserts the date and time automatically. Cheers--DO11.10 18:59, 30 November 2006 (UTC)

I have been using the signature button, and I can see my signature on these exchanges. It is highlighted in red though, so something is not right.

I solved the agreement problem by expanding the definition to include infection by multiple agents - such as occurs with HIV disease. I notice that you left "clinically evident" alone. I won't touch it for now. I understand a counter argument is that any laboratory evidence is clinical evidence, so that if the infectious agent can be detected at all, then the disease is clinically evident, however this does not square with the definition of disease, which is an impairment of host function.

Yes, I read the article you linked too as part of my research into our previous conversation. On rereading the definitions column, I like this "Invasion of the body with organisms that have the potential to cause disease" for infection, which is short and includes the possibility of including those organisms of the normal flora that have the potential, although are not usually responsible, for causing disease.

I have worked on the overview some, and rewritten it mainly to make the reading flow. Opportunistic infections are the result of a failure of host defenses, and it is important to keep in mind that the term defense does not necessarily mean the immune response, as you have addressed in your bone fracture example, however simple traumatic introduction of an infectious organism would not be commonly considered opportunistic unless there was an immune response failure. On the other hand, antimicrobials can provoke opportunistic diseases by suppressing normal gut flora, which is a non-immune system defense. So a traumatic exposure to an infectious agent that penetrates the epidermal barrier (also a passive defense) could be considered opportunistic, except if that line is crossed, then tetanus would be considered opportunistic. So although it is not exactly consistent with the strict interpretation of "failure of host defense", traumatic wound infections should not be considered opportunistic absent failure of the immune response.

I will try to enter some footnotes to references, but I don't see a button for them. I would like to enter a classification table for common opportunistic and primary pathogens. That will take some time though. --eukaryotica 16:04, 2 December 2006 (UTC)

I can't figure out how to enter the footnotes. I want to enter this: Kenneth J. Ryan and C. George Ray, Sherris Medical Microbiology Fourth Edition McGraw Hill 2004. Can you tell me how to do this? --eukaryotica 16:51, 2 December 2006 (UTC)

The introduction continued
A higlight in red just means that there is not a page with content there yet, (but I guess that you may have figued that out) they appear that way because I went through and changed them to eukaryotica which makes a link to both your user page and your talk page. As for citations you might want to read the page WP:FOOT, that gives all of the details. If there is a link to that book please include it in the reference. Yeah I think an infectious disease has to be clinically evident (with respect to laboratory findings), maybe we should include [with the potential to cause] impairment of host function?--DO11.10 17:27, 2 December 2006 (UTC)

Yes, that would be consistent. I initially put the same spacing in, but then decided against it because the Topic sentence of the paragraph introduces the two dependent subjects. I will do some more next week. You may wish to read my comment on the next section, agents and vectors. Ciao --eukaryotica 17:35, 2 December 2006 (UTC)

Still not much time t work on this, however in reading the overview I wonder what we have done for the entire article. The overview we have written offers a detailed definition but does not address the following categories. What do you think? Should we expand the overview to be a true introduction, work on the following topics to make them touch on the overview, or nothing? As it stands, the overview is better termed "definition". --eukaryotica 03:15, 9 January 2007 (UTC)
 * Sorry Eukaryotica, I have been away working on my pet project. I like your additions, good job. I have just simplified a few things and added wikilinks.
 * I definitely agree that "overview" is the wrong title for the new sections, although "definition" isn't right either (WP:MOS issues there). I suspect that it might be better to work them into the other sections in a logical manner. Something like this:


 * Types of pathogens, broadly (move "classification" here)
 * Transmission
 * Diagnosis and treatment
 * Clearance and immunity (maybe combine with "treatment")
 * Mortality
 * History and science of ID (my favorite part, definitely needs expanding) move "work of an infectologist" here.
 * Thoughts? I don't really have any clear cut opinions yet, and I would love to hear what you think.--DO11.10 23:24, 10 January 2007 (UTC)

You have done some fine work on this - the links were great to see. I presume the photos are also from your work. I have read over what I think is new and it looks very good, but I will want to go over it slowly over the next few days. OK, lets work on the sections, and when we feel it is covered we can go back to the "overview" and create a comprehensive intro that brings it all together. The definitional work we have written would be the first part of that. I think if someone came to Wiki looking just for a definition, that should be first, followed by the sort of extensive exploration of the term we are generating. I will make a first edit right now, and within a week do a closer read. I don't think immune function should be combined with treatment - one is the natural response and the other human intervention, although issues about vaccines are a bridge between the two. Morbidity and mortality links are important, since someone might come to the site with that in mind, and we could send them to MMWR or WHO. The data table will become obsolete, and so I think a link to an organization that maintains current data is more appropriate, no? The history is fascinating. You might include Lazzarro Spallanzani in your history, and I was happy to see that you didn't go afield into abiogenesis but kept focused on infectious disease. Thanks for your work. My semester just started, but it is fairly light and I will have time for this among my other projects. --eukaryotica 02:40, 19 January 2007 (UTC)

I have a number of stylistic changes to suggest, and perhaps a factual change here and there. It seems to be shaping up nicely. Perhaps the table should stay so long as current data are used. Next week. --eukaryotica 03:13, 19 January 2007 (UTC)

DO, I laid into the diagnostics part of this. I pulled the treatment out, because when I have time, I want to expand it out in the same way.--eukaryotica 02:59, 15 February 2007 (UTC)

DO, a little more work today. Maybe we should split off therapy from diagnosis. It is a pretty big section as I wrote it. If you add on, it will get even bigger. I have some photos from the student labs here that might help. I uploaded a picture I made of some plates to illustrate bacterial culture, but never used. All four are infectious agents, and Klebsiella pneumoniae and Salmonella may be recognized for their names. Should I take out the caption or pare it down? I think the thumbnail would look larger if I did.--eukaryotica 14:48, 15 February 2007 (UTC)

2007 discussion
Hi eukaryotica, Wow you have added a lot! Looks great! I will go back through and read it in depth in the next few days. As for an initial glance: Yes, that section is too big it should probably be divided up. The caption is okay as is, but ideally the content should be covered in the text with a only a fairly brief caption. I can make the image larger (and so can you! See Extended image syntax for details), that might reduce the "weightyness" of the caption as well. I will post more thoughts later. Keep up the good work!--DO11.10 04:57, 18 February 2007 (UTC) Hi DO. I moved the bulk of the caption into the text and just left a small description. I spent a few hours mainly moving words about and getting rid of red links. I put in short Gram stain and so on. I only wanted to mention a technique if it is critically significant - I could easily slip into technique. If I do so, feel free to cut it away. If you wish, start up a treatment section. I am thinking a complete list of all human pathogens would be a nice touch, don't you? It would be 100-200 entries, in table form, all linked internally. There could be reverse internal links to us from the organisms too. The only Wiki issue that came up was the (as I see it) phylum Firmicutes. Wiki refers to is as a division, and other sources do other things. I don't exactly know where the taxonomy lies, and taxonomy seems to be a source of competition for the pecking order inclined, so I just called it a group. When in doubt I prefer to conform to what Tolweb is doing, but if there is a battle, we can have division if you agree and wait for the Gods of taxonomy to sort it out in 2107. Biologists would understand phylum, and advanced biologists division, but the lay public would do better with group. --eukaryotica 17:59, 18 February 2007 (UTC)
 * The caption looks better, thanks. Haven't had time to read to much in depth here. As for the human pathogens list, that would be too large to include in this article, but would be quite useful if presented in an article called List of human pathogens, and then linking to the list on this page (you can create this article yourself by clicking on the red link, then just start typing in the box. It doesn't look like there is any sort of list like this available on Wikipedia yet). What ever presentation you think would be the most understandable to the public is probably the one that I would go with, darned scientist can't make up their mind about anything :). Hope this helps will give it a good look in a bit. Thanks again!--DO11.10 18:14, 19 February 2007 (UTC)
 * Actually, I came across this page List of infectious diseases perhaps you could expand that out, or create the pathogens page for the agent and link to the other page for the disease. Which ever you would prefer.--DO11.10 18:20, 19 February 2007 (UTC)

Great. We should link into that. It is missing a lot of obscure pathogens, but it looks very good. --199.29.206.185 21:03, 19 February 2007 (UTC)

I have had a look at the added info, and made some general copyedits (mostly to bring it to the average reader). Hopefully I haven't altered any of your intended meanings. A few big things though: Thanks again--DO11.10 22:50, 19 February 2007 (UTC)
 * Can you please proved some references for the information you have added, if you like you can provide ISBNs or PubMed ids here and I can generate the full citations which can then be added into the article. The sections on classification and transmission will also require citations.

OK. That will take some time, but I won't move forward until that is finished. --199.29.206.185 15:09, 20 February 2007 (UTC)

OK, it looks good. I appreciate the editing effort you have put in. Something threw the comparative paragraphs off, so it is hard to see exactly what changed, but in general I think the content was fully preserved. I think my biggest worry was its size. But, we could not expect to reduce infectious disease to a couple of paragraphs. 8^) A couple of contentual statements I made probably need to be pulled, such as the RNA replicase statement. While RT can and is detected as an indicator of retroviral presence, I think RNA replicase assays are not used clinically.  It was an example of difference, but implies a test.  Moving that medical history to the top puts it in its proper order - it was hanging off of the bottom, although putting it on top implies a significance for the following text it does not have.  It may as well be first, because I don't think there is any good place for it.

I can see a few syntactical agreement errors in your edit, so I will come back a little later. Thanks again DO. eukaryotica --199.29.206.185 15:28, 20 February 2007 (UTC)

Attempting to restructure this online is a problem. The meaning is sometimes lost in the proper wording of a sentence. I have printed it out and will work on it this weekend. eukaryotica --199.29.206.185 17:44, 23 February 2007 (UTC)

2009 Discussion
I changed the word disease in the first sentence to illness. It makes the prose flow better, eliminates circularity and relates to the concept of illness, of which infectious disease is a category. --eukaryotica 16:54, 20 December 2009 (UTC) —Preceding unsigned comment added by Eukaryotica (talk • contribs)

Need help on inflammatory diseases of unknown etiology
I have started a new page called inflammatory diseases of unknown etiology and would like some help answering these questions: What is the most common result for an inflammatory disease of unknown etiology? Is is labeled an immune disease? And, on what basis? What are the inflammatory diseases of unknown etiology? How many of them are there? What are the most common inflammatory diseases of unknown etiology? What kind of inflammation is associated with inflammatory diseases of unknown etiology? And how many kinds of inflammation patterns are there in inflammatory diseases of unknown etiology? What inflammatory diseases of unknown etiology have recently been proven to be infectious diseases? If anyone has the time to contribute it would be appreciated. ReasonableLogicalMan (Talk 20:55, 18 November 2007 (UTC):)

Editor recruiting
A tiny stub, Bacterial disease, is in desperate need of help. If some of the editors who are responsible for this great article would take a look at bacterial disease, I'd really appreciate it. WhatamIdoing (talk) 23:41, 14 January 2008 (UTC)

Typhoid Mary
The caption of the photo of Mary Mallon says she infected 53 people, but the Mary Mallon article says it was 47. Which was it? TimothyPilgrim (talk) 21:46, 14 February 2008 (UTC)

it was 48 —Preceding unsigned comment added by 81.137.198.141 (talk) 19:44, 24 March 2008 (UTC)

Removal of text about global warming and vector-borne diseases.
I removed the text about the effect of climate change on infectious diseases. While Global warming may alter the range of insect vectors for malaria and dengue fever, the net effect of this on incidence is considered uncertain in the IPCC Fourth Assessment Report (2007), see the [Working Group II report, chapter on Human Health], section 8.2.8, "Vector-borne, rodent-borne and other infectious diseases." Malaria has been eradicated in many areas of the world where it might naturally occur, and it is unlikely that it would return to areas with good public health systems, so the statement about Europe and North America seems quite overblown, even if some prediction occurs like that in an isolated source. The effect on malaria in sub-Saharan Africa is expected to be mixed, and the report states, "Despite the known causal links between climate and malaria transmission dynamics, there is still much uncertainty about the potential impact of climate change on malaria at local and global scales." I was originally going to edit the text to reflect what's available in the IPCC source, but decided that it was more than I could take on at this point. If the effect of climate change is to be in this article, it should better reflect the state of agreement (or controversy) that exists at this time. That there is global warming has become increasingly certain, that this is being "mostly" caused by greenhouse gases emitted by human activity is considered "very likely," that is, more than 90% likely, according to this latest IPCC report, but predicting the actual effect on vector-borne diseases isn't so simple. Warming in some areas will reduce vector populations, such as by reducing rainfall. In others, it will increase them. --Abd (talk) 00:56, 27 October 2008 (UTC)

Mary Mallon
The informational box says that she infected 53 people, but her own page says she infected 47 people. —Preceding unsigned comment added by 68.252.58.154 (talk) 22:49, 3 March 2009 (UTC)

It is worth mentioning the total number of known infectious diseases in man (which I think is currently accepted to be 1415) and that 60% of those are zoonoses somewhere within the introduction. As well as providing a breakdown of figures in terms of Bacteria 518, fungi 307, viruses 215, Prions 2, parasitic protoctists (protozoans) 66, parasitic invertebrates (helminths) 287, of which are zoonoses 868 (61%) —Preceding unsigned comment added by 86.163.69.181 (talk) 17:46, 9 January 2011 (UTC)

1415 species of infectious and parasitic organisms currently known to cause human disease
It is worth mentioning the total number of known infectious diseases in man (which I think is currently accepted to be 1415) and that 60% of those are zoonoses somewhere within the introduction. As well as providing a breakdown of figures in terms of Bacteria 518, fungi 307, viruses 215, Prions 2, parasitic protoctists (protozoans) 66, parasitic invertebrates (helminths) 287, of which are zoonoses 868 (61%) —Preceding unsigned comment added by 86.163.69.181 (talk) 17:48, 9 January 2011 (UTC)
 * Do you have a ref for this? -- Doc James (talk · contribs · email) 03:47, 16 January 2011 (UTC)

Clinically evident??
The LEDE says that an infectious disease must be a "clinically evident illness." "Clinically evident" by definition means something that can be (or could be) seen on physical examination (at the bedside) or observed by the patient, and NOT result only in a derangement of laboratory results (for example an increased antibody titer, or something culturable from skin or blood). Of course infectious diseases may be "subclinical" through most, or even all of their courses--for example, hepatitis C (often) or cytomegalovirus. And there are those people who are infected with the MRSA type of Staph but never know it, who thus have an infection (by most definitions) but without the disease. We define a "dis-ease" (of course) as something that makes you ill eventually, but there are are some infectious diseases that make people ill, if they do, only long after they have been infected. HIV is probably the most famous of these, with (historically) tuberculosis before that. With HIV, most people who are infected never notice being ill, and yet something like 85% or 90% of people with it will eventually die without treatment. But that last 10% perhaps will never be ill with it, treatment or not, and thus remain subclinical permanently, and yet also probably infectious. As was that most famous of infection-carriers Typhoid Mary, for that matter. So what do we do with this definition? I suggest inserting some qualifiers. The "illness" is USUALLY clinically-evident, but not always. Consider polio, which caused no symptoms in most children infected with it. What defines an infectious disease is that it's infectious, and it MAY cause a (clinical) disease, not that it ALWAYS causes one. S B Harris 03:37, 16 January 2011 (UTC)
 * Agree we need to fix this. Doc James  (talk · contribs · email) 03:45, 16 January 2011 (UTC)
 * I've done a little fixup. As it reads now, the clinically evident disease only occurs in the population, not every infected organism. The pathogen causes the epidemic, in the sense that without it, there is no epidemic. However, individuals can be infected and transmit the pathogen, and stay clinically fine. S  B Harris 03:56, 16 January 2011 (UTC)
 * Simplified the language a bit I hope. Doc James  (talk · contribs · email) 04:04, 16 January 2011 (UTC)
 * Yeah, almost there. The last sentence is a little screwy still, as it indirectly implies that "infectious disease" always means every individual is diseased (ill), and that is the reason why "infection" is not the same as "infectious disease". A better reason is that many (dare I say most) infections never produce any disease. And even in most infectious diseases epidemics, the "disease" is only a small tip of the iceberg of the infection itself (the classic case being polio, but we're just beginning to realize how broad the range of subclinical infection is). Everybody trades flora with everybody everywhere, all the time. It's just a few of the bugs that make anybody sick, and even of those, a great many only make a tiny fraction of their hosts seriously or noticably sick. The main factor in all of this, is usually how much evolutionary "time" the pathogen has been in humans, from wherever else it came from. If it's "new" to humans (like a new zoonosis) it has a very high morbidity. If it's been with humans a long, long time, it may have almost no morbitity (statistically) at all. Or (like CMV) it manifests itself only in immunocompromised hosts, but not in others who merely transmit it. S  B Harris 04:33, 16 January 2011 (UTC)
 * Agree completely lots of those with both the common cold and dengue fever are asymtomatic. And disease like syphilis have long periods of no symptoms but the person still has a infectious disease. Feel free to improve further. Doc James (talk · contribs · email) 05:28, 16 January 2011 (UTC)

History section is deficient
The history section of the article is deficient..... Would be nice to have a listing of infectious diseases with links to their pages along with short accounts of the disease, its effects, and how to treat it. More than I can do, but perhaps a useful project for someone who has a better background.

Avram Primack (talk) 15:09, 7 October 2011 (UTC)

Infectious vs. communicable
The lead states that the class of infectious diseases includes the class of communicable diseases, and readers would be excused for interpreting that to mean that "infectious disease" is a more general notion than "communicable disease." But nowhere in the article do we elaborate—or indeed even come close to clarifying—that distinction.

This kind of problem in a Wikipedia article is bad enough; it's aggravated when, as here, the suggested-but-unexplained nuance involves a redirection. Those who look up "communicable disease" find themselves deposited onto an article about "infectious disease" with only a hint of why.

I'd fix the flaw myself but... guess what!... what brought me to the article in the first place was the desire to learn the very distinction that the article fails to explain!

Lots of discussion here on the talk page about communicability and infectiousness, but nothing definitive and clear. And besides, talk pages are not where Wikipedia's users are supposed to have to look to find substantive information about the topic of interest.

Would somebody who is qualified please fix this fundamental flaw in the lead.—PaulTanenbaum (talk) 20:14, 4 April 2012 (UTC)


 * Good point. In fact, the problem appears to be spreading.  The situation over at Non-communicable disease and Non-infectious disease (two articles that say they are about the same thing) is also rather a mess.
 * Also, this article didn't seem to even have a link to and Contagious disease (yet another similar term).
 * In both cases the relation needs to be made clearer. If non-communicable and non-infectious are the same, then those articles should be merged.
 * I don't think infectious and contagious mean the same thing. However if infectious and contagious are the same, then contagious disease should be merged into this article; and if they aren't this one should be corrected to clarify/maintain the distinction.
 * I haven't found a good source covering the matter. Zodon (talk) 21:15, 4 April 2012 (UTC)
 * Since Non-communicable disease and Non-infectious disease said they were about the same thing, I merged them to Non-communicable disease. That article still needs some cleanup after the merge. Zodon (talk) 08:16, 6 April 2012 (UTC)

Infectious, transmissable, and communicable diseases are all the same thing, and more or less synonyms. In the past a distinction was made between diseases that were infectious/communicable/transmissable, but not especially so (like tuburculosis), and those that were *very* infectious, like influenza. The word for the latter was "contageous" and these diseases were responsible for contageons = epidemics. Of course, this is a spectrum with no place to draw a bright line. The distinction is not often used these days, although we have transmissable diseases where the victims are not isolated (like HIV/AIDS), and these are generally not classically contageous (yet still of course communicable, as all diseases caused by living organisms are. Heart disease is not communicable). Malaria and yellow fever are other classic examples of transmissible and communicable, but not contageous, diseases. They are indirectly communicable, but still communicable. If that helps. I've fixed up the lede to help make the (historical) distinction clear. S B Harris 22:02, 6 April 2012 (UTC)