Talk:Hobo spider

Distribution map contradicts article text

The article says they are native to Europe but the distribution map only shows them inhabiting the Pacific Northwest of the US, and part of Canada. —Preceding unsigned comment added by Radishes (talk • contribs) 20:19, 10 September 2007 (UTC)

The map shown is just the distribution within North America. I don't know who supplied the graphic, or any way to mark it to indicate that it omits that NATIVE range. Dyanega 21:39, 10 September 2007 (UTC)

It is also missing that they are now in Alaska. —Preceding unsigned comment added by 66.230.110.137 (talk) 08:03, 28 September 2007 (UTC)

Do you have an authoritative citation for this? Dyanega 17:48, 28 September 2007 (UTC)

untitled

I'd like to see a reference to the trial involving rabbits, because it sounds alot like a survey of directly opposite results referenced on the UC Davis page. The necrosis seems to be septic rather than posionous, according to these guys.

This article was clearly written by someone who particularly likes this type of spider. It ought to be revised by someone who has more experience with these spiders, as it is currently inconsistent with other information on the web about the hobo spider.

--A reader

Study of the article history will show that quite a few people have contributed to this article. There has been a great deal of misinformation about this spider on the WWW and maybe in other places. The University of California at Riverside article (see link at the bottom of the article) is quite objective and was written by professionals in the field.

Nobody would enjoy being bitten by these spiders. If I had to choose, I'd much rather be bitten by a 5" Huntsman. Pain is one thing, and necrotic tissue damage is something else. That being said, they are not nearly as damaging to humans as are the brown recluse spiders, and the real champion killer, world wide, is still the genus Latrodectus. There are worse spiders to be bitten by, especially the venomous funnel-web spiders of Australia, but the widow spiders manage to kill more people simply because there are so many more of them building their nests in places where people will stick their hands or other parts of their anatomies.

Nobody I've ever read has indicated any particular affection for this kind of spider. The medical sources that collect data on bites and consequences do not pretend that these spiders can't or won't bite, nor do any of them maintain that the bites provoke nothing more than a momentary unpleasantness. On the other hand, one should not let one's subjective reaction to a rather unappealing-looking spider with a medically significant bite blind one to a clear awareness of the relative degree of threat they pose to humans.P0M

The article link recently added, Discover Magazine, is not nearly as good as the articles it cites. The author of the Discover article has only a M.F.A. from the University of Arkansas, and has written some secondary materials on black widows. The article on the hobo spiders starts with the account of a death, but it is not clear what spider or other agent was the cause of the death. Then it gives an account of a serious bite case where the spider was collected and identified. That's a sort of journalistic "bait and switch" IMHO. I'm rather surprised at Discover for publishing the article. The Riverside site and the hobospider.com site both mention deaths, but they don't sensationalize the deaths. I think it is the Riverside site that mentions one death in which the spider bite was a contributory cause. That kind of reporting is much more sober and responsible. Do we really want to direct people to sensationalistic articles? P0M 05:09, 20 September 2005 (UTC)

I was concerned about citing Discover, believe me.  :) The reason for the link is not for the sensationalist content--if anything, the changes I made to the article support the case that maybe the hobo isn't as bad as thought. The reason for the link was to reference some of the work of Greta Binford, some of which I haven't found a better reference for (such as her repeat of Vest's experiments). I have found one referenced to a relevant Binford paper (on her home page), which I will include. --EngineerScotty 16:45, 20 September 2005 (UTC)

This article's treatment section seems to be heavily geared toward home treatment based on internet advice. I've changed this to refer a reader to professional medical consultation, as messing with necrotic tissue with only the inconsistent wisdom of the 'net in one's layman's arsenal seems foolish at the very best.

-user thescathed

You can sign by using four tildes like this: ~~~~.

Thanks for bringing this matter to our attention. The advice is wrong on a couple of counts. The main thing that is wrong with it is suggesting that people "cut off necrosis." I guess that means the writer imagines somebody going after necrotic tissue with a razor blade or an x-acto knife. Bad idea! I don't like the idea of putting a greasy antibiotic ointment on a puncture wound either. A buffered iodine solution would be more likely to get down to any microbes or viruses deep within the wound. P0M 05:09, 16 July 2006 (UTC)

"hobospiders.org" not truly an "independent organization"

It is worth noting that the website "hobospiders.org" was created and maintained by Darwin K. Vest, the author whose original rabbit skin toxicology study is the basis for all subsequent claims of medical significance for this spider. Calling it an "independent organization" is disingenuous; it is a single individual whose personal reputation is at stake if the claims of toxicity are false, and therefore must be treated as a potentially biased source of information, and readers should be made aware of this conflict of interests. To date, the original research has not been supported by independent researchers, nor replicated. It is not a controversy at the level of cold fusion, but it is a fundamentally similar situation; a single researcher publishes a study making certain claims, numerous others accept the results of the study, and it becomes public knowledge and propagated by the media, but later independent attempts to confirm the study all fail. While it may yet prove to be that hobo spider venom is dangerous, at this stage any such claims should be considered highly suspect, and it is important that this page reflect these facts as objectively as possible. Potential editors of this article need to exercise caution and vigilance accordingly, as non-professionals who read websites like hobospiders.org are likely to constantly attempt to edit the article to a more sensationalized form. Dyanega 18:27, 28 September 2006 (UTC)

First and foremost: You should realize that Darwin Vest is missing and presumed dead, so he most certainly isn't maintaining that site. While some of your concerns are perhaps warranted (there have been many instances of various forms of pathological science proclaiming spiders species to be dangerous, only for further research to discover otherwise--the hobo is only one example of this phenomenon), the above strkes me as a rather disingenious--and unfair--attack on Vest's reputation. To compare him to Martin Fleischmann and Stanley Pons is outrageous. Vest's research has been published in peer-reviewed journals; he has not engaged in the dubious practice of announcing new findings at press conferences. While it may eventually be superceded and/or contradicted by subsequent research (Greta Binford at Lewis and Clark College has been unable to replicate his experiments), suggesting that Vest is in a "fundamentally similar situation" to Fleishmann and Pons, who have been accused of gross sloppiness, is an unwarranted smear. I'm not aware of Vest ever being accused of any sort of scientific misconduct or incompetence. It's perferctly reasonable to question a scientists's findings, after all, without impugning his reputation, and it may be that Binford and others are right, and Vest was wrong. But the above strikes me as a hatchet job. If you have evidence that Vest has acted unprofessionally, by all means, post it. --EngineerScotty 19:19, 28 September 2006 (UTC)

I am saying his research cannot be repeated, and is therefore questionable. That's science in a nutshell.

Agreed.

If you interpret that as "attacking his reputation" then that is your interpretation.

What I was concerned about were the references to cold fusion; a situation where findings were promoted in the press in advance of any peer review--a significant breach of scientific protocol. Vest, to my knowledge, hasn't made claims in non-reviewed forums that didn't correspond to his peer-reviewed research (or the research of others). And obviously, he shouldn't be held responsible for the current contents of the site--being dead, he has little control over it.  :) Fleischmann and Pons have been severly criticized for their methods--comparing a scientist to them (or their work to the cold fusion debacle) is easily interpreted as a smear. THAT is what I objected to; not to the suggestion that Vest's work may turn out to have been flawed in some manner. (That's why peer review is done, after all...)

I'm a professional scientist, a reviewer for over 20 journals dealing with insects and other arthropods, and I understand that things can get published that are not true, not because of "misconduct or incompetence", but simple error. If I had stated that Vest's work was *intentionally* fraudulent, that would be an attack, and I make no such claims. I claim that there is reason not to trust the original research, nor to continue accepting it at face value. That much is demonstrable.

I agree; this article should document the issue as much as possible.

These spiders may be harmless, and people need to be educated as to that possibility, rather than presenting pages like hobospiders.org without rebuttal to the claims made there. It's really quite straightforward. The only "unprofessional" thing I see is the hobospiders website itself, which treats the issue of necrotic wounds being caused by hobos as a given fact, rather than something unproven. It does say "Text and Photographs by Darwin K. Vest" on the website, after all - but just because he believed it to be true does not make it true, nor merit promoting it *as* true in the face of contrary evidence. I think we can agree on that. Dyanega 20:33, 28 September 2006 (UTC)

Pretty much. Unfortunately, hobospiders.org is these days being maintained, near as I can tell, by non-scientists. Being related to a scientist doesn't make you one. Your original paragraph above made it sound that Vest himself was running the site to promote his work in extrascientific forums, despite mounting evidence to the contrary coming from within science. As he's most likely dead, that's obviously not true. Many of the questions concerning hobo venom have been raised since his disappearance, so it's highly likely that he believed that hobospiders.org contained valid and sound research during the time that he controlled it. At any rate, I'm for strenghtening the disclaimer on the site's reference in the external links section (and am glad that it isn't used to back up any claims in this article). I think we are in agreement on substance; and have only minor disagreement on tone. --EngineerScotty 20:49, 28 September 2006 (UTC)

NPOV?

This article has way too much crap about whether or not the bite is necrotizing. Can't someone condense the stuff in the article to, oh, about a 5 sentence paragraph with references that a reader can visit for more information? This reads like it's someone's pet topic.

The subject matter of this article is CONTROVERSIAL. A five-sentence paragraph is not going to be able to present all the claims and evidence from both sides of the controversy, and the point of WP is so people DON'T have to look elsewhere for references - THIS page is where it should be collated and summarized, and that is why there is so much "crap" presented here. Especially true when - as in this case - nearly all of the websites one can find easily promote the unproven claims. What would be a violation of NPOV is to eliminate the discussion via condensation. —The preceding unsigned comment was added by Dyanega (talk • contribs) 19:25, 11 December 2006 (UTC).

There really does seem to be a huge bias in the presentation of the information in the two flagged sections (agressiveness and avoiding bites). It struck me quite strongly and felt overtly critical. I almost feel the need to put the weasal word flag on the aggressiveness section for the way it has been written. Both sections need to be reconstructed such that they present information from a "despite popular opinion, the data supporting such claims is inconclusive" perspective instead of wholly undercutting the current state of research. 81.201.56.15 06:24, 9 September 2007 (UTC)

You seem to misunderstand - the current state of research is that the bites are rare, non-necrotic, and the spiders are not aggressive or dangerous. This is amply documented and referenced throughout. The original study appears to be quackery, but it's better to be polite about it and say that there is no evidence to support it, and that attempts to repeat it have failed. The harsh tone helps to combat misinformation that the typical reader has been exposed to, and possibly even to prevent well-meaning would-be editors from constantly trying to change the article to make it sound like hobo spiders ARE dangerous, when all the evidence is piling up that they are NOT. Part of this comes down to undue weight concerns; it would misrepresent the controversy to give the "hobo spider is dangerous" theory equal weight with the numerous studies and pieces of evidence that indicate it is not. Vest's theory qualifies as a fringe theory, held by a tiny minority of experts, against a vastly larger body of experts that dismiss the theory. Therefore, if the fringe theory is to be cited at all, it needs to be cited with explicit reference to the aspects which qualify it as a fringe theory. Dyanega 06:42, 9 September 2007 (UTC)

Here's an article about a research group trying to determine if the hobo spider's gettin' a bad rap.[1] — Scientizzle 18:51, 21 September 2007 (UTC)

"Medically significant" is quit opposite the ranting and raving about this spider's harmlessness. I just caught one of these spiders in a jar. What should I feed it, to keep it alive long enough to send it to Dyanega, who apparently is volunteering to let it bite him/her? Checking http://encarta.msn.com/encyclopedia_761566464_6/Spider_(arthropod).html I see the sentence "Bites from these spiders can be fatal to humans without proper treatment." Seems pretty small-minded to try minimizing the severity of a resultant bite, no? My camera is currently broken, but the spider I just caught, I caught on the same wall where that previous one was (that I photographed long ago.) Offhand, I'd guess this specimen is a direct descendant of the one I photographed. (Apologies for the poor picture - I was too close when I took it, but the preview looked fine. By the time I zoomed and cropped, that specimen was already converted to an even blurrier - but harmless - smudge.) --Connel MacKenzie - wikt 06:22, 1 November 2007 (UTC)

The only reason that there is anything in this article about Hobo bites being medically significant is because it got into print that they were - Wikipedia cites all published opinions, even ones that have no evidence to back them up. Dyanega 16:31, 1 November 2007 (UTC)

I don't know why people are disputing this. Ask anyone who's been bitten by a Hobo Spider and they will tell you exactly what happens. It is not fun. My mother was bitten several years ago by one and the site definitely turned necrotic and to this day is still tender to the touch. Lost Cosmonaut (talk) 18:25, 22 April 2008 (UTC)

Hobo spiders definitely cause necrosis in some humans. Plenty of reports tell you that. I think it's just not safe to say it causes necrosis in all humans. Different breeds of rabbits showed immunity; it'd make sense that different races of humans would show immunity. Either way, I'm cleaning up the article. Taking out some redundant statements and condensing it a little, but leaving the overall message and disputed effects there. Fllmtlchcb (talk) 23:22, 3 June 2008 (UTC)

Looking up more sources shows that only one confirmed instance of necrosis in humans exist. As far as your mother, sorry to hear, but it wasn't a hobo spider, says the facts. Fllmtlchcb (talk) 11:32, 4 June 2008 (UTC)

Please tell me what spider or insect is common in the Pacific Northwest that does cause necrosis? Because she was definitely bit by something, and our house (my wife and I now live where my parents did) is usually full of Hobo spiders (our three most common spiders are various species of jumping spiders, common house spiders and Hobos), and where we live we don't commonly get Black Widows (too cold, but they do occur to our east as my father has been bit by one before) and Brown Recluses are thousands of miles away. I know it's one thing to look at studies and empirical evidence, but just because studies haven't "proved" something doesn't mean it DOESN'T happen, just that it hasn't been studied enough yet. Show me a study where people actually volunteered to get bit and didn't have necrosis and I will say that it's possible Hobos do not cause necrosis with their bites. All I know is I have talked with several people in the area who have been bitten by spiders that can only be identified as Hobo spiders that have also had a similar necrosis of the bites. 204.14.96.6 (talk) 05:17, 26 June 2008 (UTC) Sorry, wasn't signed in. Lost Cosmonaut (talk) 05:19, 26 June 2008 (UTC)

I cannot tell you what arthropod in the NW causes necrotic wounds because there are none known. You have NEVER seen a spider bite you, I'm betting. Neither have any of your FOAF's. In 30+ years in the business, I have yet to meet a person who SAW a spider bite them. Without that direct evidence, and a captured specimen of the offending spider, it's all just as likely as alien abductions, ESP, and Bigfoot. Dyanega (talk) 13:50, 26 June 2008 (UTC)

Are you saying my mother is a crackpot? Awesome. I saw the wound, it was quite the sight. None of us have ever had necrosis before or after this case, but none of us have been bitten by spiders recently. The only time I've ever been bitten by a spider the response was very minor, about the same as a mosquito which means it was probably a jumping spider since those are very common and have a minor bite. Like I said, there was definitely necrosis of the wound. She had no other damage at the site through which necrosis could happen randomly. My father and I are always cutting and wounding ourselves on things inside and outside of the house doing various chores and work and have never had a necrotic response. Comparing it to Bigfoot, Alien abductions and ESP is laughable because there is physical evidence that necrosis DID happen. Sure, we can't trace it back to an origin (it happened while she was asleep, and a dead spider matching the markings and physical characteristics of a hobo spider was found at the foot of her bed between the sheets) but the fact is there WAS necrosis of the wound which still affects her even to this day. If the necrosis was caused by an environmental issue then I got much more problems in the house than a few little hobo spiders. Lost Cosmonaut (talk) 17:18, 26 June 2008 (UTC)

Necrosis can be caused by LOTS of things: Lyme disease, Stevens-Johnson syndrome, toxic epidermal necrolysis (Lyells syndrome), G.C. arthritis dermatitis, erythema multiforme, infected herpes simplex, erythema nodosum, chronic herpes simplex, purpura fulminans, diabetic ulcer, bed sores, poison ivy/oak infection, focal vasiculitis, thromboembolic phenomena, periarteritis nodosa, lymphomatoid papulosis, pyoderma gangrenosum, sporotrichosis, warfarin poisoning, and Rocky Mountain Spotted Fever. I am sure that neither you, your mother, nor your mother's doctor has ruled out ALL of those possible causes. Yet, ALL of them are MORE common than spider bites. So, you're picking the LEAST likely out of a long list of possible causes. You'll forgive me if I don't believe a spider caused your mother's necrotic wound - because there are so many possible causes.

Also, empirical evidence or not there is something to be said for anecdotal "folk" evidence. SOMETHING in this area causes necrotic wounds, and there is an abundance of Hobo Spiders in this area. Hobo spiders have been linked for years now to a necrotic wound. Why would everyone link the two if there wasn't something to it? It makes me laugh that some of the comments in this discussion have alluded that the Hobo spider has been "maligned". Fact is, it is a funnel web spider which are known to cause some nasty wounds and have some painful bites. Some of the "deadliest" spiders in the world are funnel-webs, like the Atrax robustus which has quite the reputation in Australia. Everyone links necrotic wounds after a spider bite to the Hobo. Just because science can't PROVE that there is necrosis in connection with a Hobo bite doesn't mean it DOESN'T happen. And unlike alien abductions, bigfoot and ESP, there IS physical evidence of damage. Lost Cosmonaut (talk) 17:26, 26 June 2008 (UTC)

Unfortunately, you don't seem to understand how science and medicine work. Usually, people come to Wikipedia to learn what scientists say, not to argue with them. Dyanega (talk) 20:12, 26 June 2008 (UTC)

Alright, I believe that I have offered the article an NPOV. It covers both sides of the dispute. Let me know if there's something missing, and I'll personally go look up sources and rectify the article. Fllmtlchcb (talk) 00:05, 4 June 2008 (UTC)

There sure is something missing. A single confirmed case of necrosis in a healthy human. You state "Hobo spiders definitely cause necrosis in some humans. Plenty of reports tell you that." Please give ONE citation. "Reports" that do not actually involve a spider caught in the act of biting are NOT data points, and NOT reliable sources. Darwin Vest's rabbit study IS NOT PROOF that hobo spiders induce necrotic wounds in humans. It's really that simple. NPOV demands that extraordinary claims require evidence; the claim that these spiders are dangerous is extraordinary, and has NO evidence to date. There is nothing "definite" about this except that a lot of people say a lot of things with nothing to back their claims up. The claims can be cited in Wikipedia, but to slant the article as if these claims are valid is a violation of NPOV. Dyanega (talk) 02:54, 4 June 2008 (UTC)

Then I'll fix it some more. My edits to that part of the article merely condensed the article to take out redundant statements and offer a little organization. Now I'll go back and fact-check. So far, only one confirmed report of necrosis in humans exists in a patient that already had necrotising skin. I'll keep that in there, but make explicit notice that no other suck cases exist. Fllmtlchcb (talk) 11:22, 4 June 2008 (UTC)

Doing research, it seems that only the one extreme case exists, so I took out all mention of necrosis except for that case. It seems that all points of view are neutral now, so anyone against me removing the NPOV flag?

Even if we can't agree as to whether or not there is necrosis of the bite, a warning of some sort should still be in place. Necrosis or not, they are still not something you want to take lightly. 204.14.96.6 (talk) 05:17, 26 June 2008 (UTC) Sorry, wasn't signed in. Lost Cosmonaut (talk) 05:19, 26 June 2008 (UTC)

Wikipedia isn't the place to warn people of a non-existent threat. The article very clearly says what their bites cause. What happened to your mother is not known. It is your word against every spider specialist in the world, and they say there aren't any verified cases. Stop arguing about what happened with your mother. Without pictures and the spider in question, we can't really take what you say as fact. Nothing personal, but that's just the way this place works. Fllmtlchcb (talk) 22:54, 27 June 2008 (UTC)

Giving undue weight to anecdotes and non-authorities

I'll say it again for clarification for all the people who prefer to trust outdated and/or non-authoritative sources: Wikipedia is not here to promote theories; if there are competing theories, then both sides are presented according to the number and reliability of sources, and the evidence behind both theories is presented objectively. To treat two hypotheses as equal when one theory has no evidence to support it is considered undue weight, and POV-pushing to favor the weaker hypothesis. There is no objective evidence, nor are there authoritative sources, to support the claim that hobo spider bites are medically significant - it's on a par with the old tale that putting pencil leads in your mouth would give you lead poisoning. There are literally dozens of controlled, peer-reviewed studies on the composition and medically significant effects of the venom of widow spiders, dozens more on the venom of brown recluses, and ZERO on the venom of hobo spiders. These spiders have co-habited with human beings in Europe for centuries, and yet there have been no confirmed medically significant bites there. As in the U.S., the only reports of necrotic wounds in Europe that have been associated with hobo bites are those where no one ever actually saw a spider, and (also as in the U.S.) ALL these reports post-date Darwin Vest's original - and still unconfirmed - suggestion that hobo bites were a source of necrotic wounds. If the absence of supporting evidence is not enough to make one stop and reconsider the urban legends, consider this: to date, not a single authority on spiders or spider bites has come forward to support the claim. The only ones that have come forward have done so to state exactly the OPPOSITE. Surely, after more than a decade since Vest's report, there would be ONE legitimate authority who would have come along and said "Yes, the bites of this spider are medically significant". You can try a simple experiment: if your doctor tells you that hobo bites are dangerous, just ask him whose research, published in what medical journal, he learned this from. You'll find that doctors are just as vulnerable to urban legends as the next person. The bottom line is simple: the authorities are saying that there is no reason to believe that hobo bites are dangerous. The WP article reflects what the authorities have to say; that's WP policy. Dyanega 17:26, 1 November 2007 (UTC)

Errors, etc...

I'm fairly new here so please bear with me as I learn the ropes.

First of all, the sources that I have found contradict the stated frequency of dry bites. All credible sources I have seen indicate a 50% rate of dry bites, not "in the majority of cases" as is indicated by the article. Upon checking the citation for the statement I found no indication of that being reiterated or any such supporting information on the burke museum webpage that was linked to as citation number 3. Further as can be seen in the works of Gretta Binford and other prominents in the field, it is actually quite difficult to determine the frequency of dry bites for a huge multitude of reasons. Such factors include measuring venom should it be present, should there be a threshold quantity that qualifies as a "wet" bite if the amount injected isn't clinically significant, access of bite victims to medical and scientific services necessary to detect, identify, and measure the venom, etc...

Another error exists in the citation and subsequent extrapolation from the Darwin Vest rabbit study. In the article it states that the rabbits were injected with hobo venom, which was not the case. In the Vest study the spiders were simply held against the skin of the rabbit. The study did not milk and subsequently inject the venom as purported in the article. A followup study done by Gretta Binford while at Arizona University and published in part in Toxicon did milk the spiders and injected the venom. In this study the results of the Vest study were not duplicated. The Vest study is further cast into doubt knowing that they did not inject the venom, meaning that statistically, if it is true that about 50% of bites are dry, then he should have had fewer cases of necrotic reaction than reported.

Additionally, the 8th citation made, also to burke museum, to support the statement "Hobo spiders are common in Europe, though bites are relatively unknown, and do not cause necrosis" is incorrect. The linked page never mentions the bite rates of Hobo's in Europe or whether they cause necrosis or not. On a further note, after reviewing much of the information on the burke museum spider webiste I have found much of their information to be ex termly biased, inaccurate, and in some cases out of date. I wouldn't use it as a source on my blog, let alone a wikipedia article.

There also seems to be some disagreement on whether the bite of the hobo can cause a necrotic reaction. First of all, there is no evidence that the components of hobo venom should cause a necrotic reaction as can be seen from the work of Matt Fidorea, Gretta Binford and others. This doesn't mean that an unknown agent doesn't exist as a secretion on the surface of the spider that could contaminate the injection site. Also, research is ongoing as to whether or not reactions from spider bites could be made worse by the bacteria that spiders may carry. Recently it is believed that spiders may carry certain types of bacteria that are harmful to humans, and a bite would be an excellent method of transmission. Not strictly related to the topic of necrosis is the hemolytic properties of the venom. The Yellow Sac Spider and Giant House Spider venom has a hemolytic rate of 89% while the Hobo has a rate of 1% to 1.2%. Again, this doesn't eliminate the possibility of a necrotic reaction, but it illustrates the damaging properties of the Hobo venom as compared to other, clinically insignificant spiders.

It is also believed by some that the necrotic reaction is not directly caused by the venom of the Hobo spider. Protease within the venom have been shown to elicit an especially strong immune response in humans. This causes immediate swelling in the area. In some cases, based on local physiology, as well as the state of the immune system in the person and their predisposition to react, the swelling could constrict the area around the bite. This could cause a loss of blood flow to the dead tissue, creating an anaerobic environment. Once this is created infection from anaerobic bacteria could become responsible for a necrotic reaction.

Moving beyond the academics of this discussion I do believe that the "tone" of the article is inappropriate in that it imparts opinion. Multiple sides on a controversial topic should have the arguments of all sides laid out without a sympathetic tone. It is this tone that initially caused me to take a break from work and write up this response. I apologize for not having more sources, I am at work.

The section on toxicity and aggressiveness, beyond having too much of a tone, provides too much unsupported information as fact. Specifically "Hobo spider bites are not known to be fatal to healthy humans" which isn't cited and in direct conflict with other sources. While I do doubt these sources, there are purported cases of Hobo bites causing bone marrow failure and renal failure resulting in death. Personally, I believe it more likely that the bite, if really a bite at all, was miss attributed to the Hobo. But there are educational research institutions that state this information on their site and without my own studies to duplicate their research who am I to arbitrarily dismiss them just because i find them unlikely.

I also disagree with the bite treatment section. I feel that it should be emphasized that the proper course of action in any medical situation is to seek medical attention, no matter how trivial. If a person does indeed capture the spider that they know is responsible then is it unlikely that the doctor can properly identify the spider. To do so would require examination under a microscope. Determination of sex and development could also give an indication of the severity of any toxin injected. I also disagree with the statement "applied on the off chance that the bite introduced a virus or microbe". I think that the use of "off chance" is both too casual of a tone and also implies uncited information. It would seem to imply that it is unlikely that the bite introduced foreign matter but does not cite a source. It should simply instruct to apply a disinfectant. Also, spraying the wound with something such as bactine *may* be more effective at penetrating the wound than an ointment.

All in all I would recommend that the article rating be changed from a 'B' to a 'C' based on all of this information, lack of citations, and unrelated citations. —Preceding unsigned comment added by Krellor (talk • contribs) 22:12, 5 August 2008 (UTC)

Reading over your message, I've made the correction you note regarding Vest using spiders to bite the rabbits, versus Binford's injection protocol. Other suggested changes will, of course, require citations. For the Burke Museum source, for example, all that would be required to refute a statement such as "Hobo spiders are common in Europe, though bites are relatively unknown, and do not cause necrosis" is ONE study from Europe showing that these spiders do bite, and that they cause necrosis. I've yet to come across any such references, so if you know of one, please link it here. Likewise, you claim that the statement "Hobo spider bites are not known to be fatal to healthy humans" is contradicted by other sources, yet you give no such sources. All it would take is ONE credible cite. Please, if you have reliable sources with contradictory information, please link them here, and if they necessitate a change to the article, then they can be included. If the sources are not reliable (you say "While I do doubt these sources"), then perhaps they do not deserve to be given credence, especially if the opinion of experts in the field all unanimously disagree. While you may be correct in the bias of the Burke website, it is written by an expert, and there are no experts which appear to be disagreeing; if there are "two sides" to an issue, they don't have to be given equal weight if their evidence and arguments are not equal - that's an essential aspect of NPOV, to NOT expect "equal weight" when there is a fundamental asymmetry. Having interacted with many spider experts, I find that they tend to be extremely insulted by the constant barrage of disbelief they get from laymen who insist things like "Brown recluses live in California" and "A hobo spider bite gave me a necrotic wound" simply because their doctors made a mistaken diagnosis. The spider experts get defensive, and much of what they write, be it websites or otherwise, reflects that. The unanimous opinion from spider experts is that you cannot diagnose a wound as being caused by a spider simply by its symptoms, and you cannot FURTHER extrapolate by blaming a spider that either doesn't even occur in your area, or does not have sufficient medical evidence supporting claims of its venom's properties. As for the bite treatment section, your comments don't seem unreasonable, but again, having some sort of citation would be preferrable - I'm half-tempted to just delete most or all of that section, as it is. It treads a fine line, since "giving medical advice" in WP is something to be avoided, or at least treated with care and circumspection. Dyanega (talk) 00:32, 6 August 2008 (UTC)

I apologize if the formatting of my reply is not correct, I am unfamiliar with the wiki interface. I will gather some sources for my statements, but I do think you misunderstand what I am saying about the burke museum site. That one page is cited twice. The first time to support the claim that the majority of bites are dry and later that hobo spiders do not bite in europe and do not cause necrosis. The linked page never mentions either of those pieces of information. I'm not saying that the information is wrong, just that the citation is inaccurate. The citation may as well link to dilbert in regards to those two pieces of information.

Source that states "up to half of bites are dry" http://whatcom.wsu.edu/ag/homehort/pest/hobo.html

I can provide additional sources for that figure if necessary.

As far as causing necrosis in europe versus the PNW the article has some ambiguity.

As far as the behavior of European Hobo Spiders, they will bite if they feel threatened like any other member of the species. The lack of cases in europe is because they have been displaced from common human dwellings by the Giant House spider. Just because there are fewer encounters with the spider doesn't make them less likely to bite if threatened, such as if they became trapped in someones pants. It is just that in europe a hiker is more likely to have an encounter than a housewife. Also, you cannot differentiate the effects of the venom based on location of the spider. Examination of the venoms with liquid chromatography and insect bioassays revealed no difference between the two population groups, meaning that the venom is identical in Europe as in the US. (Binford, 2001: http://www.sciencedirect.com/science?_ob=MiamiImageURL&_imagekey=B6TCS-42D2BP0-6-F&_cdi=5178&_user=137179&_check=y&_orig=search&_coverDate=07%2F01%2F2001&view=c&wchp=dGLbVzz-zSkWz&md5=5503d563a16e7f28cb3c5ac4f4064dbc&ie=/sdarticle.pdf)

The article shouldn't attempt to differentiate effects of the bite based on geographic region when all information shows no difference between the venom based on geography.

Another source of ambiguity is the definition of "necrosis". In the Vest study he defined necrosis as any ulceration of the skin. (Rick Vetter, 2004 "However, his case definition of “necrotic arachnidism” appears arbitrary and is based on the appearance of a skin lesion." http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WB0-4CVV6JP-3&_user=137179&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000011439&_version=1&_urlVersion=0&_userid=137179&md5=4fe5df7ae5239832cb697b60854d7c86)

Because of this arbitrary definition of necrosis by Vest it is impossible to contrast his findings with medical cases of necrotic arachnidism. Because of this, rather than say that there are purported cases of necrotic reactions in the US versus europe, you could instead expound on the difference in definition of what constitutes a necrotic reaction. You could mention the purported case, but point out the definition of necrosis used to highlight the difference between the studies definition, the medical definition ("the morphological changes indicative of cell death caused by progressive enzymatic degradation; it may affect groups of cells or part of a structure or an organ."), and the common impression given to the layman when talking about necrosis.

This brings me to the portion of the article "The only documented case of a verified hobo spider bite leading to necrotic skin lesions involves a person who had a pre-existing medical condition that also leads to necrotic skin lesions". This is slightly misleading. The verified case involved a 42 year old woman who had a history of phlebitis. While phlebitis does have a possible, rare, symptom of breakdown of skin cells, I wouldn't necessarily describe the condition as "leading" to it. I might change it to "that also has skin lesions as a side effect". Maybe this seems overly pedantic, but it makes sense to me.

As to my claims of bone marrow failure, I will provide sources. But let me clarify two things first. One, I don't like all of the sources. Two, even the sources that I do like I do not agree with the findings. It is also important to understand the difference between spider bite and spider poisoning. http://hobospider.com/info/index.html http://hobospider.org/poison.html http://www.fs.fed.us/r1/fire/nrcg/Committees/Operations/ims/ims_web_site/Hobo%20Spider.htm http://209.85.173.104/search?q=cache:EpUTAA_EfsoJ:www.sheridan.edu/msha/Powerpoint/Dangerous%2520Critters.ppt+hobo+spider+bone+marrow+failure&hl=en&ct=clnk&cd=9&gl=us&client=firefox-a (tranlation of http://www.sheridan.edu/msha/Powerpoint/Dangerous%20Critters.ppt)

Most of these sources indirectly cite "http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WB0-4DW8HFM-C&_user=137179&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_version=1&_urlVersion=0&_userid=137179&md5=b021ed7db540312f2168a85e87eed94d". This study examines Loxoscelism, of which hobo poisoning would fall into. However, this doesn't mean that a hobo is capable of severe Loxoscelism. That is why I said I take exception to the sources. Some of the sources would appear to be credible, or at least should be (Government, .edu) but I disagree with their inclusion of the data in regards to the hobo. But again, my opinion on the matter isn't inherently more important than theirs.

I wish I had more time to respond, but at the moment I have a meeting to go to.

Krellor (talk) 15:58, 6 August 2008 (UTC)

Another quick little note. You wrote "For the Burke Museum source, for example, all that would be required to refute a statement such as "Hobo spiders are common in Europe, though bites are relatively unknown, and do not cause necrosis" is ONE study from Europe showing that these spiders do bite, and that they cause necrosis."

What I was saying about the burke site is that it does not say anywhere that hobos are common in europe, that the bites are relatively unknown, or that they do not cause necrosis. The citation is just plain wrong, so please, find a better source to cite for the statement. I'm not trying to refute the information, I'm simply saying that the citation is wrong. I also think that the specific denial of necrosis in a specific geographical area could be confusing. Krellor (talk) 18:48, 6 August 2008 (UTC)

I've made most of the changes you suggest. A point of clarification: when you wrote "The article shouldn't attempt to differentiate effects of the bite based on geographic region when all information shows no difference between the venom based on geography." I think something has gotten confused there. What I had thought the Binford study made clear is that hobo venom is the same in the US and Europe. That is one fact. Second is that no one in Europe has ever reported a necrotic bite from a hobo (this is one of those awkward situations where it is difficult to prove the negative, but the review papers certainly give no such citations, and if the experts can't find any records of necrotic hobo bites in Europe, then it does not seem unfair to state that there are no such reports). However, connecting those two facts together would apparently constitute "original research" (i.e., if the article were to make the logical connection that if hobo bites WERE necrotic, then we would have had reports from Europe - and that we never have is evidence that the belief that the venom is necrotic is false). Unless Binford et al. specifically stated that the reports of necrotic bites from the US must be spurious, then no matter how logical, the article still shouldn't express that conclusion. As for the four links you gave, one is Vest's own website (NOT a reliable source), and the other three all refer to Vest's laboratory study, either directly or by citing a work that cites it. if the original lab study is dubious, then ALL of these links are just as dubious, as they are secondary sources which supply no additional evidence beyond that rabbit-injection study; they simply cite it as if it were a fait accompli. Dyanega (talk) 21:05, 9 August 2008 (UTC)

I think we are on the same page for the most part. I agree with your conclusion regarding the Europe statement. I was more or less just trying to point out that it may seem confusing to a reader if the purported effects of the venom differed based on geography; that it might give the impression that the venom is different when it is not. Just trying to point out a possible point of confusion.

Now, one thing that could be stated is that analysis of the venom has revealed no known mechanism to cause necrosis. If you do not have any, then I can provide sources to support this. It may not seem like it because of some of my picking, but I do not believe that hobo venom causes necrosis, that only in the rarest of cases and because of contamination could a hobo bite cause necrosis (in the sense that a rose thorn can cause necrosis because it is coated with necrotizing fungus). But I will still pick at information if it doesn't have a citation.  :) As far as the bone marrow failure claim, etc... I believe I specifically said I didn't agree with them. However, my last source, regarding treatment of Loxoscelism includes Hobo spiders. "Loxosceles spiders are the only globally distributed arachnid species capable of causing necrotizing skin lesions. Rarely, a more severe systemic reaction can occur, causing hemolysis, with subsequent renal failure and significant morbidity. There is no cost- or time-effective diagnostic test to confirm envenomation and no definitive treatment."

I would support excluding information tying the Hobo to severe Loxoscelism, even though they are often included in papers on the subject, primarily because there is no evidence linking Hobo's specifically to severe Loxoscelism. However, I felt it important to provide an opposing viewpoint to the article, if for no other reason than to provide a discussion on the topic in the discussion page. And I like to play Devils advocate from time to time. On a final note if you haven't, I would recomending reading the 2001 Binford study in its entirety. Here is a paragraph of specific interest.

(After discounting three other possible discrepancies in purported cases between Europe and the PNW)

"A final possible explanation is that T. agrestis are not directly or indirectly the cause of necrosis and have been falsely accused. Misdiagnosis of spider bites is a well known and common issue (Russell and Gertsch, 1983; Kunkel, 1985; Rosenstein and Kramer, 1987; Kemp, 1990; Vest, 1993b; Vetter and Visscher, 1998). Agents that create symptoms that are often confused with spider bites are discussed in the above references, and range from reactions to other organisms (arthropods, such as the lyme disease vectors (Ixodes spp.); fungal dermatophytes; viruses; bacterial infections), to systemic reactions to underlying medical problems (leukemia, infections). Nonetheless, Vest (1993b) advises: ªThe tentative diagnosis of necrotic arachnidism should be considered in any clinical case in which deep, slow-healing necrotic lesions develop, with or without systemic manifestations, unless clear evidence of another cause can be demonstratedº. There are a number of reasons why Vest's advice to diagnose necrotic arachnidism as a default is not reasonable. First, there are no definitive diagnostic characteristics that are absolutely and uniquely associated with the bite of a given spider, making accurate diagnosis of spider bites dependent on retrieval and identification of spiders that were seen biting the victim (Russell and Gertsch, 1983). The author is aware of only one case in the literature where a T. agrestis individual was directly linked to a bite which allegedly led to a necrotic lesion (Vest, 1987a; Akre and Myhre, 1991; Fisher et al., G.J. Binford / Toxicon 39 (2001) 955±968 965 1994; Vest, 1996). Even this case is doubtful because the victim did not seek medical assistance (and presumably spider identification) for 79 days after the bite (Case 2, Vest, 1996)."