View source for Spider bite

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{{For|the urban legend|The Spider Bite}}
{{Infobox disease
 | Name            = Spider bite
 | Image           = Black Wishbone.jpg
 | Caption         = [[Chelicerae]] of a [[Aname atra|black wishbone]] ([[Nemesiidae|nemesiid]]) spider, a [[Mygalomorphae|mygalomorph]].
 | Field           = [[Emergency medicine]]
 | DiseasesDB      =12299
 | ICD10           = {{ICD10|T|14|1|t|08}}{{·}}{{ICD10|T|63|3|t|51}}<br/>{{nowrap|W57 (nonvenomous)}}<br/>{{nowrap|X21 (venomous)}}
 | ICD9            = {{ICD9|989.5}}{{·}}{{ICD9|E905.1}}{{·}}{{ICD9|E906.4}}
 | ICDO            =
 | OMIM            =
 | MedlinePlus     = 002858
 | eMedicineSubj   = article
 | eMedicineTopic  = 772484
}}

==Overview==

<!-- Definition and symptoms -->
A '''spider bite''', also known as '''arachnidism''', is an injury resulting from the bite of a [[spider]]. The effects of most bites are not serious.<ref name=Lancet2011>{{cite journal|last1=Isbister|first1=GK|last2=Fan|first2=HW|title=Spider bite.|journal=Lancet|date=10 December 2011|volume=378|issue=9808|pages=2039–47|pmid=21762981|doi=10.1016/s0140-6736(10)62230-1}}</ref> Most bites result in mild symptoms around the area of the bite.<ref name=Lancet2011/> Rarely they may produce a necrotic skin wound or severe pain.<ref name="Andrews">{{cite book |author=James, William D.; Berger, Timothy G.; et al. |title=Andrews' Diseases of the Skin: clinical Dermatology |publisher=Saunders Elsevier |location= |year=2006 |pages= |isbn=0-7216-2921-0 |oclc= |doi= |accessdate=}}</ref>{{rp|455}}

<!-- Cause -->
Most spiders do not cause bites that are of importance.<ref name=Lancet2011/> For a bite to be significant, substantial [[envenomation]] is required. Bites from the [[Latrodectus|widow spider]]s involve a neurotoxic venom which produces a condition known as [[latrodectism]].<ref>{{cite journal |last=Braitberg |first=George |year=2009 |title=spider bites: Assessment and management |journal=Australian Family Physician |volume=38|issue=11|pages=862–67 |url=http://www.racgp.org.au/afp/200911/200911braithberg.pdf}}</ref> Symptoms may include: pain which may be at the bite or involve the chest and abdomen, sweating, muscle cramps and vomiting among others.<ref name=Lancet2011/> Bites from the [[recluse spider]]s cause the condition [[loxoscelism]], in which local [[necrosis]] of the surrounding skin and widespread [[hemolysis|breakdown of red blood cells]] may occur.<ref name=Swanson2005>{{cite journal|last1=Swanson|first1=DL|last2=Vetter|first2=RS|title=Bites of brown recluse spiders and suspected necrotic arachnidism.|journal=The New England Journal of Medicine|date=17 February 2005|volume=352|issue=7|pages=700–7|pmid=15716564|doi=10.1056/nejmra041184}}</ref> Headaches, vomiting and a mild fever may also occur.<ref name=Swanson2005/> Other spiders that can cause significant bites include: the Australian funnel web spiders,<ref>{{cite journal|last1=Isbister|first1=GK|last2=Gray|first2=MR|last3=Balit|first3=CR|last4=Raven|first4=RJ|last5=Stokes|first5=BJ|last6=Porges|first6=K|last7=Tankel|first7=AS|last8=Turner|first8=E|last9=White|first9=J|last10=Fisher|first10=MM|title=Funnel-web spider bite: a systematic review of recorded clinical cases.|journal=The Medical journal of Australia|date=18 April 2005|volume=182|issue=8|pages=407–11|pmid=15850438}}</ref> the [[South American wandering spider]],<ref name=Lancet2011/> and the [[hobo spider]].<ref name=CDC2012W>{{cite web|title=Workplace Safety & Health Topics Venomous Spiders|url=http://www.cdc.gov/niosh/topics/spiders/|website=cdc.gov|accessdate=15 February 2015|date=February 24, 2012}}</ref>

<!-- Prevention and treatment -->
Efforts to prevent bites include clearing clutter and the use of [[pesticide]]s.<ref name=Lancet2011/> Most spider bites are managed with supportive care such as [[NSAIDs]] (including [[ibuprofen]]) for pain and [[antihistamine]]s for itchiness.<ref name=Kang2014/> [[Opioids]] may be used if the pain is severe.<ref name=Kang2014/> While an [[antivenom]] exists for black widow spider venom it is associated with [[anaphylaxis]] and therefore not commonly used in the United States.<ref name=Kang2014/> Antivenom against funnel web spider venom improves outcomes.<ref name=Lancet2011/> Surgery may be required to repair the area of injured skin from some recluse bites.<ref name=Kang2014>{{cite journal|last1=Kang|first1=JK|last2=Bhate|first2=C|last3=Schwartz|first3=RA|title=Spiders in dermatology.|journal=Seminars in cutaneous medicine and surgery|date=September 2014|volume=33|issue=3|pages=123–7|pmid=25577851|url=http://admin.imng.com/fileadmin/content_pdf/san/scms_pdf/Vol_33_Iss_3_SPIDERS_IN_DERM.pdf|doi=10.12788/j.sder.0107}}</ref>

<!-- Epidemiology and history-->
Spider bites may be overdiagnosed or misdiagnosed.<ref name=Lancet2011/> Historically a number of conditions were attributed to spider bites. In the Middle Ages a condition claimed to arise from spider bites was [[tarantism]], where people danced wildly.<ref>{{cite journal|last1=Donaldson|first1=LJ|last2=Cavanagh|first2=J|last3=Rankin|first3=J|title=The dancing plague: a public health conundrum.|journal=Public health|date=July 1997|volume=111|issue=4|pages=201–4|pmid=9242030|doi=10.1016/s0033-3506(97)00034-6}}</ref> While necrosis has been attributed to the bites of a number of spiders, good evidence only supports this for recluse spiders.<ref name=Lancet2011/>

==Signs and symptoms==
[[File:BrownRecuse1.jpg|thumb|A Brazilian man 31 hours after having been bitten on his face by a [[recluse spider]]]]
[[File:BrownRecuse2.jpg|thumb|4 months after a brown recluse spider bite with scar remaining]]
Almost all spiders are venomous, but not all spider bites result in the injection of venom. Pain from non-venomous, so-called "dry bites" typically lasts for 5 to 60&nbsp;minutes while pain from envenomating spider bites may last for longer than 24&nbsp;hours.<ref name="GFD2010">{{cite web |url=http://www.globalfamilydoctor.com/search/GFDSearch.asp?itemNum=12031&ContType=HDA |title=Global Family Doctor - Wonca Online &#124; Item search |format= |work= |accessdate=}}</ref> Bleeding also may occur with a bite. Signs of a bacterial infection due to a spider bite occur infrequently (0.9%).<ref name="GFD2010" />

A study of 750 definite spider bites in Australia indicated that 6% of spider bites cause significant effects, the vast majority of these being [[redback spider]] bites causing significant pain lasting more than 24 hours.<ref>{{cite journal |author=Isbister GK, Gray MR |title=A prospective study of 750 definite spider bites, with expert spider identification |journal=QJM |volume=95 |issue=11 |pages=723–31 |date=November 2002 |pmid=12391384 |doi= 10.1093/qjmed/95.11.723|url=}}</ref> Activation of the sympathetic nervous system can lead to sweating, high blood pressure and gooseflesh.<ref>{{cite journal|last1=Offerman|first1=SR|last2=Daubert|first2=GP|last3=Clark|first3=RF|title=The treatment of black widow spider envenomation with antivenin latrodectus mactans: a case series.|journal=The Permanente journal|date=Summer 2011|volume=15|issue=3|pages=76–81|pmid=22058673}}</ref>

Most [[recluse spider]] bites are minor with little or no necrosis. However, a small number of bites produce necrotic skin lesions.  First pain and tenderness at the site begin. The redness changes over 2 to 3 days to a bluish sinking patch of dead skin—the hallmark of necrosis. The wound heals slowly over months but usually completely.<ref>{{cite news|last1=Sandlin|first1=Nina|title=Convenient culprit: Myths surround the brown recluse spider|url=http://www.amednews.com/article/20020805/health/308059999/4/|accessdate=2 March 2015|agency=American Medical News|publisher=American Medical Association|date=5 August 2002}}</ref> and, rarely, widespread symptoms, including profound anemia.  Rarely the bite may also produce the systemic condition with occasional fatalities<ref name="Vetter2013">{{cite journal|last1=Vetter|first1=RS|title=Spider envenomation in North America.|journal=Critical care nursing clinics of North America|date=June 2013|volume=25|issue=2|pages=205–23|pmid=23692939|doi=10.1016/j.ccell.2013.02.006}}</ref>

==Cause==
{{Main|List of medically significant spider bites}}
Spiders do not feed on humans and typically bites occur as a defense mechanism.<ref name=CDC2012W/> This can occur with from unintentional contact or trapping of the spider.<ref name=CDC2012W/> Most spiders have fangs too small to penetrate human skin.<ref name=Diaz2004/> Most bites by species large enough for their bites to be noticeable will have no serious medical consequences.<ref>{{cite web | last = | first = | title =Spider Bite First Aid  | publisher = firstaidkits.org | url =http://www.firstaidkits.org/spider-bites.asp | accessdate = 2007-08-23}}</ref>

Medically significant spider venoms include various combinations and concentrations of [[Necrosis|necrotic]] agents, [[neurotoxins]], and pharmacologically active compounds such as serotonin. Worldwide only two spider venoms have impact on humans—those of the widow and recluse spiders. Unlike snake and scorpion envenomation,<ref>{{cite journal|last1=Chippaux|first1=JP|last2=Goyffon|first2=M|title=Epidemiology of scorpionism: a global appraisal.|journal=Acta tropica|date=August 2008|volume=107|issue=2|pages=71–9|doi=10.1016/j.actatropica.2008.05.021|pmid=18579104}}</ref> widow and recluse species bites rarely have fatal consequences. However, isolated spider families have a lethal neurotoxic venom: the wandering spider in Brazil and the funnel web in Australia. However, due to limited contact of humans with these spiders, deaths have always been rare, and since  the introduction of anti-venom in Australia, there have been no funnel web related deaths.<ref name="ReferenceA">{{cite journal|last1=Isbister|first1=GK|last2=Gray|first2=MR|title=Bites by Australian mygalomorph spiders (Araneae, Mygalomorphae), including funnel-web spiders (Atracinae) and mouse spiders (Actinopodidae: Missulena spp).|journal=Toxicon : official journal of the International Society on Toxinology|date=February 2004|volume=43|issue=2|pages=133–40|pmid=15019472|doi=10.1016/j.toxicon.2003.11.009}}</ref>

==Pathophysiology==
{{Main|Pathophysiology of spider bites}}
A primary concern of the bite of a spider is the effect of its [[venom]]. A spider envenomation occurs whenever a spider injects [[venom]] into the skin. Not all spider bites involve injection of venom, and the amount of venom injected can vary based on the type of spider and the circumstances of the encounter.  The mechanical injury from a spider bite is not a serious concern for humans.  However, it is generally the toxicity of spider venom that poses the most risk to human beings; several spiders are known to have venom that can cause injury to humans in the amounts that a spider could inject when biting.
While venoms are by definition toxic substances, most spiders do not have venom that is directly toxic (in the quantities delivered) to require medical attention and, of those that do, severity is typically mild.

Spider venoms work on one of two fundamental principles; they are either neurotoxic (attacking the nervous system) or necrotic (attacking tissues surrounding the bite). In some cases, the venom affects vital organs and systems.  The venoms of the widow spiders, Brazilian wandering spider and Australian funnel-web are neurotoxic. Heart muscle damage is an unusual complications of widow venom that may lead to death.<ref>{{cite journal|last1=Erdur|first1=B|last2=Turkcuer|first2=I|last3=Bukiran|first3=A|last4=Kuru|first4=O|last5=Varol|first5=I|title=Uncommon cardiovascular manifestations after a Latrodectus bite.|journal=The American journal of emergency medicine|date=February 2007|volume=25|issue=2|pages=232–5|pmid=17276832|doi=10.1016/j.ajem.2006.11.005}}</ref> Pulmonary edema, fluid acumulation in the lungs, is a feared uncommon complication of funnel-web venom.<ref name="ReferenceA"/> Recluse and South African sand spider venoms are necrotic. Recluse venom may also cause severe hemolysis (destruction of red blood cells)<ref>{{cite journal|last1=Manríquez|first1=JJ|last2=Silva|first2=S|title=[Cutaneous and visceral loxoscelism: a systematic review].|journal=Revista chilena de infectologia : organo oficial de la Sociedad Chilena de Infectologia|date=October 2009|volume=26|issue=5|pages=420–32|pmid=19915750}}</ref>

==Diagnosis==
Assumption that a reported injury was caused by a spider is the most common source of false reports, which in some cases have led to misdiagnosis and mistreatment, with potentially life-threatening consequences.<ref name="autogenerated1">{{Cite journal | doi = 10.1136/ewjm.173.5.357 | last1 = Vetter | first1 = R. S. | year = 2000 | title = Myth: idiopathic wounds are often due to brown recluse or other spider bites throughout the United States | url = | journal = [[Western Journal of Medicine]] | volume = 173 | issue = 5| pages = 357–358 | pmid=11069881 | pmc = 1071166}}</ref> Many spider bites are relatively painless but the spider is often trapped and easily found.  With neurotoxic envenomation, serious symptoms arise within a few hours.

An affected person may think that a wound is a spider bite when it is actually an infection with [[methicillin-resistant Staphylococcus aureus|methicillin-resistant ''Staphylococcus aureus'']] (MRSA).<ref>{{cite web|title=Methicillin-resistant Staphylococcus aureus (MRSA) Infections|url=http://www.cdc.gov/mrsa/community/|website=cdc.gov|accessdate=15 February 2015|date=September 10, 2013}}</ref>

Spider bites are commonly misdiagnosed. Unverified bite reports are frequent and likely represent many other conditions, both infectious and non-infectious can be confused with spider bites.<ref>{{cite journal | doi = 10.1636/RSt08-06.1 | last1 = Vetter | first1 = R.S. | year = 2008 | title = Spiders of the genus ''Loxosceles'' (Araneae, Sicariidae): a review of biological, medical and psychological aspects regarding envenomations | url = | journal = The Journal of Arachnology | volume = 36 | issue = | pages = 150–163 }}</ref> Many of these conditions are far more common and more likely to be the source of necrotic wounds.<ref name=Swanson2005/>

==Management==
Most spider bites are harmless, and require no specific treatment. Treatment of bites may depend on the type of spider; thus, capture of the spider—either alive, or in a well-preserved condition, is useful.<ref>[http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Spiders Spiders], Retrieved December 1, 2013</ref><ref>[http://dermnetnz.org/arthropods/spider-bites.html Spider bites], Retrieved December 1, 2013</ref>

Treatment of spider bites includes washing the wound with soap and water and ice to reduce inflammation.<ref name=Diaz2007>{{cite journal|last1=Diaz|first1=JH|last2=Leblanc|first2=KE|title=Common spider bites.|journal=American family physician|date=15 March 2007|volume=75|issue=6|pages=869–73|pmid=17390599}}</ref> [[Analgesics]] and [[antihistamines]] may be used, however antibiotics are not recommended unless there is also a [[bacterial infection]] present.<ref name=Diaz2007/> Treatment of black widow envenomation seeks to control the pain and nausea that result.

In the case of bites by [[widow spider]]s, [[Australian funnel-web spider]]s, or [[Brazilian wandering spider]]s, medical attention should be sought as in some cases the bites of these spiders develop into a [[medical emergency]].<ref>[http://www.nlm.nih.gov/medlineplus/ency/article/002858.htm Spider bites: First aid], Retrieved December 1, 2013</ref><ref>{{cite web|title=Spider Bites|url=http://www.healthdirect.gov.au/spider-bites|website=Health Direct Australia}}</ref> Antivenom is available for severe widow and funnel-web envenomation.<ref name="Lancet2011"/>

===Necrosis===
In almost all cases, recluse bites are self-limited and typically heal without any medical intervention.<ref name=Swanson2005/> Recommendations to limit the extent of damage include elevation and immobilization of the affected limb, application of ice. Both local wound care, and [[tetanus prophylaxis]] are simple standards.  There is no established treatment for more extensive [[necrosis]]. Many  therapies have been used  including [[hyperbaric oxygen]], [[dapsone]], antihistamines (e.g., [[cyproheptadine]]), [[antibiotics]], [[dextran]], [[glucocorticoids]], vasodilators, [[heparin]], [[nitroglycerin]], [[electric shock]], [[curettage]], [[surgery|surgical excision]], and [[antivenom]]. None of these treatments conclusively show benefit. Studies have shown surgical intervention is ineffective and may worsen outcome. Excision may delay wound healing, cause [[abscesses]], and lead to objectionable scarring.<ref name="AnnSurg1985-Rees">{{cite journal | author = Rees R, Altenbern D, Lynch J, King L | title = Brown recluse spider bites. A comparison of early surgical excision versus dapsone and delayed surgical excision | journal = Ann Surg | volume = 202 | issue = 5 | pages = 659&ndash;63 | year = 1985 | pmid = 4051613 | pmc = 1250983 | doi = 10.1097/00000658-198511000-00020}}</ref>

[[Dapsone]], an antibiotic, is commonly used in the [[USA]] and [[Brazil]] for the treatment of necrosis. There have been conflicting reports with some supporting its efficacy and others have suggested it should no longer be used routinely, if at all.<ref name="AmJEmergMed2003-Bryant">{{cite journal | author = Bryant S, Pittman L | title = Dapsone use in Loxosceles reclusa envenomation: is there an indication? | journal = Am J Emerg Med | volume = 21 | issue = 1 | pages = 89&ndash;90 | year = 2003 | pmid = 12563594 | doi = 10.1053/ajem.2003.50021}}</ref>

===Antivenom===
Use of [[antivenom]] for severe spider bites may be indicated, especially in the case of neurotoxic venoms.<ref name="pmid19457345">{{cite journal |author=Espino-Solis GP, Riaño-Umbarila L, Becerril B, Possani LD |title=Antidotes against venomous animals: state of the art and prospectives |journal=Journal of Proteomics |volume=72 |issue=2 |pages=183–99 |date=March 2009 |pmid=19457345 |doi=10.1016/j.jprot.2009.01.020 |url=}}</ref> Effective antivenoms exist for ''Latrodectus'', ''Atrax'', and ''Phoneutria'' venom. In the United States antivenom is intravenous but is used rarely as anaphylactic reaction to the antivenom has resulted in deaths. In Australia, intramuscular antivenom was commonly used, but the use has declined. Doubt has been raised bout the effectiveness of  antivenom<ref>{{cite journal|last1=Isbister|first1=GK|last2=Page|first2=CB|last3=Buckley|first3=NA|last4=Fatovich|first4=DM|last5=Pascu|first5=O|last6=MacDonald|first6=SP|last7=Calver|first7=LA|last8=Brown|first8=SG|last9=RAVE|first9=Investigators|title=Randomized controlled trial of intravenous antivenom versus placebo for latrodectism: the second Redback Antivenom Evaluation (RAVE-II) study.|journal=Annals of Emergency Medicine|date=December 2014|volume=64|issue=6|pages=620–8.e2|pmid=24999282|doi=10.1016/j.annemergmed.2014.06.006}}</ref><ref>{{cite journal|pmid=12864719 | volume=179 | title=Latrodectism: a prospective cohort study of bites by formally identified redback spiders | date=July 2003 | author=Isbister GK, Gray MR | pages=88–91}}</ref> An antivenom for ''Loxosceles'' bites is available in South America, and it appears antivenom may be the most promising therapy. However, the recluse antivenom is more effective in experimental animals when given early,  patients do not often present until 24 or more hours after the event, possibly limiting the effect of this intervention.<ref name="ClinTox2003-Isbister">{{cite journal | author = Isbister G, Graudins A, White J, Warrell D | title = Antivenom treatment in arachnidism | journal = J Toxicol Clin Toxicol | volume = 41 | issue = 3 | pages = 291&ndash;300 | year = 2003 | pmid = 12807312 | doi = 10.1081/CLT-120021114}}</ref>

==Epidemiology==
Estimating the number of spider bites that occur is difficult as the spider involvement may not be confirmed or identified.<ref name=Diaz2004>{{cite journal|last1=Diaz|first1=JH|title=The global epidemiology, syndromic classification, management, and prevention of spider bites.|journal=The American journal of tropical medicine and hygiene|date=August 2004|volume=71|issue=2|pages=239–50|pmid=15306718}}</ref> Several researchers recommend only evaluating verified bites: those that have an eyewitness to the bite, the spider is brought in, and identified by expert. With "suspected arachnidism" the diagnosis came without a spider positively identified.<ref name=Swanson2005/>

===Africa===
Several ''Latrodectus spp'' (button spiders) live in Africa. South Africa also has the six-eyed sand spider that may cause skin necrosis. Physicians are advised that the diagnosis may be difficult without a spider.<ref>{{cite journal | author = Muller GJ, Wium CA, Marks C, Plessis CE, Veale DJ | year = 2012 | title = Spider bite in southern Africa: diagnosis and management | url = | journal = CME. | volume = 30 | issue = 10| pages = 382–391 }}</ref>

===Australia===
Bites by the redbacks (''Latrodectus hasselti'') number a few thousand yearly throughout the country. Antivenom use is frequent but declining<ref>{{cite journal|last1=Isbister|first1=GK|last2=Gray|first2=MR|title=Latrodectism: a prospective cohort study of bites by formally identified redback spiders.|journal=The Medical journal of Australia|date=21 July 2003|volume=179|issue=2|pages=88–91|pmid=12864719}}</ref> Children may have less complications of bite.<ref>{{cite journal|last1=MEAD|first1=H. J.|last2=JELINEK|first2=G. A.|title=Red-back spider bites to Perth children, 1979-1988|journal=Journal of Paediatrics and Child Health|date=August 1993|volume=29|issue=4|pages=305–308|doi=10.1111/j.1440-1754.1993.tb00518.x}}</ref> Funnel web spider bites are few 30-40 per year and 10% requiring intervention. The Sydney funnel web and related species are only on the east coast of Australia.<ref>{{cite journal|last1=Braitberg|first1=G|last2=Segal|first2=L|title=Spider bites - Assessment and management.|journal=Australian family physician|date=November 2009|volume=38|issue=11|pages=862–7|pmid=19893831}}</ref><ref>{{cite journal|last1=Isbister|first1=G.K.|title=A prospective study of 750 definite spider bites, with expert spider identification|journal=QJM|date=1 November 2002|volume=95|issue=11|pages=723–731|doi=10.1093/qjmed/95.11.723|pmid=12391384}}</ref>

===Europe===
In Switzerland about ten to one hundred spider bites occur per one million people per year.<ref>{{cite journal|last1=Nentwig|first1=Wolfgang|last2=Gnädinger|first2=Markus|last3=Fuchs|first3=Joan|last4=Ceschi|first4=Alessandro|title=A two year study of verified spider bites in Switzerland and a review of the European spider bite literature|journal=Toxicon|date=October 2013|volume=73|pages=104–110|doi=10.1016/j.toxicon.2013.07.010}}</ref> During epidemics of latrodectism from the European black widow upwards of 150 bites/year were documented.<ref>{{cite journal|last1=BETTINI|first1=S|title=EPIDEMIOLOGY OF LATRODECTISM.|journal=Toxicon : official journal of the International Society on Toxinology|date=October 1964|volume=104|pages=93–102|pmid=14301291}}</ref>

===North America===
The American Association of Poison Control Centers reported that they received calls regarding nearly 10,000 spider bites in 1994.<ref name=Diaz2004/> The spiders of most concern in North America are [[brown recluse spider]]s, with nearly 1500 bites in 2013<ref name="AAPC 2012">{{cite journal|last1=Mowry|first1=James B.|last2=Spyker|first2=Daniel A.|last3=Cantilena|first3=Louis R.|last4=McMillan|first4=Naya|last5=Ford|first5=Marsha|title=2013 Annual Report of the American Association of Poison Control Centers’ National Poison Data System (NPDS): 31st Annual Report|journal=Clinical Toxicology|date=December 2014|volume=52|issue=10|pages=1032–1283|doi=10.3109/15563650.2014.987397}}</ref> and [[Latrodectus|black widow spiders]] with 1800 bites.<ref name="AAPC 2012"/> The native habitat of brown recluse spiders is in the southern and central United States, as far north as Iowa. Encounters with brown recluse  outside this native region is very rare and bites are thought to be suspect.<ref name=Swanson2005/> A dozen major complications were reported in 2013.<ref name="AAPC 2012"/><ref name="CPCS">[http://www.calpoison.org/public/spiders.html#4 The California Poison Control System > Spider bites], managed by the University of California. Retrieved July 2010</ref>

===South America===
Numerous spider bites are recorded in Brazil with 5000/ annually. Loxosceles species are responsible for the majority of reports. Accidents are concentrated in the southern state of Parana with rates as high as 1/1000 people.<ref>{{cite journal|last1=Marques-da-Silva|first1=E.|last2=Souza-Santos|first2=R.|last3=Fischer|first3=M. L.|last4=Rubio|first4=G. B. G.|title=Loxosceles spider bites in the state of Paraná, Brazil: 1993-2000|journal=Journal of Venomous Animals and Toxins including Tropical Diseases|date=2006|volume=12|issue=1|doi=10.1590/S1678-91992006000100009}}</ref> Bite from Phoneutria (Brazilian wandering spider) number in the thousands with most being mild. Severe effects are noted in 0.5% of cases, mostly in children.<ref>{{cite journal|last1=BUCARETCHI|first1=Fábio|last2=DEUS REINALDO|first2=Cláudia Regina de|last3=HYSLOP|first3=Stephen|last4=MADUREIRA|first4=Paulo Roberto|last5=DE CAPITANI|first5=Eduardo Mello|last6=VIEIRA|first6=Ronan José|title=A clinico-epidemiological study of bites by spiders of the genus Phoneutria|journal=Revista do Instituto de Medicina Tropical de São Paulo|date=February 2000|volume=42|issue=1|doi=10.1590/S0036-46652000000100003}}</ref>

==Historical remedies==
Recorded treatment from the 1890s for spider bites in general was rubbing in [[tobacco juice]] to the bitten skin,<ref>{{cite wikisource | class=book| first= Wilhelmina |last=Rawson | chapter = |  wslink = Australian enquiry book of household and general information | title = Australian Enquiry Book of Household and General Information | year = 1894 | page =165 <!-- | wspage = 169 not working yet-->  | publisher = Pater & Knapton, Printers & Publishers | issn = | scan = Page:Australian enquiry book of household and general information.djvu/169}}</ref> similar to some of the traditional uses of the tobacco plant for various bites and stings from Central and South America.<ref>{{cite journal|last=Binorkar|first=Sandeep|author2=Jani, Dilip |url=http://www.scopemed.org/fulltextpdf.php?mno=18268 |title=Traditional Medicinal Usage of Tobacco &#8211; A Review|journal=Spatula DD - Peer Reviewed Journal on Complementary Medicine and Drug Discovery|date=1 January 2012|volume=2|issue=2|pages=127–34|doi=10.5455/spatula.20120423103016}}</ref> Wild dancing and music was the cure for [[tarantism]]—the erotic frenzy believed to arise from the bite of a spider.<ref>{{cite web|title=Tarantism: Form of Hysteria|url=http://www.britannica.com/EBchecked/topic/583346/tarantism|publisher=Encyclopedia Britannica|accessdate=22 March 2015}}</ref> An antivenom was developed against wolf spiders in Brazil and used for decades. Wolf spiders have since been exonerated—they never caused illness.<ref>{{cite web|last1=Crawford|first1=Rod|title=Myths, Misconceptions, and Superstitions About Spiders|url=http://www.burkemuseum.org/spidermyth/|website=Burke Museum|publisher=University of Washington|accessdate=22 March 2015}}</ref>

==See also==
*[[ArachnoServer]] database
* [[Raventoxin]]
* [[Vanillotoxin]]

==References==
{{Reflist|2}}

== External links ==
*[http://www.mja.com.au/public/issues/182_08_180405/isb10564_fm.html Medical Journal of Australia article gives statistics on the most frequent biters and the most serious bites.]
*[http://www.badspiderbites.com/spider-bite.php Pictures and descriptions of spider bites from around the world.]
*[http://spiders.ucr.edu/dermatol.html Richard S. Vetter and P. Kirk Visscher of the University of California at Riverside]
*[http://www.dbskeptic.com/2008/02/03/spider-bites-are-an-overrated-menace/ Spider bites are an overrated menace]
*[http://www.themrsa.com/how-to-tell-the-difference-between-mrsa-and-a-spider-bite/ How to Tell the Difference between MRSA and a Spider Bite]
*[http://www.cdc.gov/niosh/topics/spiders/ CDC - Venomous Spiders - NIOSH Workplace Safety and Health Topic]

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{{General injuries}}
{{Poisoning and toxicity}}
{{Animal bites and stings}}

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[[Category:Animal attacks]]
[[Category:Parasitic infestations, stings, and bites of the skin]]
[[Category:Spiders]]
[[Category:Toxic effects of venomous animals]]
[[Category:Venomous animals]]