II. Definitions

  1. Arachnidism
    1. Toxic effect of venom of Spider (Spider Envenomation)

III. Pathophysiology

  1. Spiders are Arachnids (8 legged arthropods) along with mites and ticks

IV. Precautions

  1. "Spider Bites" are typically not due to Spiders, but rather other causes (e.g. MRSA Cellulitis)
  2. Most Spider Bites are benign (not black widow or brown recluse)
    1. Need only minimal local therapy (Wound Cleansing, cold therapy)
    2. Although all Spiders are venomous, very few Spiders have fangs long enough to penetrate human skin

V. Types: Most toxic Spiders (worldwide)

  1. Spiders in U.S.
    1. Black Widow Spider Bite (lactrodectism)
      1. Medium size black Spider (up to 4 cm) with a red or yellow hourglass on the Abdomen
      2. Typically found in outdoor spaces (or basements, garages, sheds)
    2. Brown Recluse Spider Bite (Loxoscelism)
      1. Small Spider (up to 2 cm) with a dark violin shaped pattern on the anterior thorax
      2. Typically found in indoor, quiet spaces (e.g. furniture, clothes, bedsheets)
    3. Wolf Spider
    4. Red Legged Widow Spider (Red Widow Spider, Lactrodectus bisophi)
      1. Rare relative to Black Widow Spider found in Florida
    5. Yellow sac Spider or Common Sac Spider (Cheiracanthium inclusum)
    6. Brown Widow Spider (Lactrodectus geometricus)
      1. Causes lactrodectism, similar to Black Widow Spider, red back Spider, katipo
      2. Originally found in Africa and South America, but have also been found in U.S. (e.g. California)
    7. Tarantula Bite
  2. Spiders outside U.S.
    1. Brazilian Wandering Spider (Phoneutria fera, Phoneutria nigriventer)
      1. Most neurologically active venom
    2. Siz-Eyed Sand Spider
      1. Southern Africa Spider (related to Brown Recluse Spider)
    3. Chilean Recluse Spider (arana de rincon, aranha-marrom, corner Spider)
      1. Most dangerous of the Recluse Spiders
    4. Redback Spider (Lactrodectus hasselti)
      1. Black widow relative, primarily found in Australia (and invasive to New Zealand, Belgium, Japan via Grapes)
    5. Northern Funnel Web Spider (Dipluridae family)
      1. Australian Spider
      2. Among the most poisonous Spiders worldwide
    6. Sydney Funnel Web Spider (Dipluridae family)
      1. Australian Spider
  3. References
    1. Encyclopedia Britannica (accessed online)
      1. https://www.britannica.com/list/9-of-the-worlds-deadliest-spiders

VI. Types: Spiders without significant bite reactions (U.S.)

  1. Orb Weaver (Araneus)
  2. Garden Spider (Argiope)
  3. Trap door Spider (Bothriocytum)
  4. Mouse Spider (Drassodes)
  5. Parson Spider (Herpyllus)
  6. Huntsman Spider (Heteropoda)
  7. Running Spider (Liocranoides)
  8. Wolf Spider (Lycosa)
  9. Crab Spider (Misumenoides)
  10. Barn Spider (Neoscona)
  11. Green lynx Spider (Peucetia)
  12. Jumping Spider (Phiddipus)
  13. False Black Widow Spider (Steatoda)
  14. Trap door Spider (Ummidia)

VII. History

  1. Circumstances of bite (e.g. garage, basement) and timing of bite
  2. Characteristics of biting Spider (coloration, size, markings)
  3. Anatomic location of bite
  4. Associated local and systemic symptoms

VIII. Findings

  1. See Black Widow Spider Bite (lactrodectism)
  2. See Brown Recluse Spider Bite (Loxoscelism)
  3. General
    1. Solitary Papule, Pustule or wheal

X. Labs

  1. Based on suspected bite type
  2. See Black Widow Spider Bite (lactrodectism)
  3. See Brown Recluse Spider Bite (Loxoscelism)

XI. Prevention

  1. See Prevention of Vector-borne Infection
  2. Check clothes for Insects before donning
  3. Flick Spiders off skin instead of crushing against skin
  4. Avoid habitats
    1. Woodpiles
    2. Crawl spaces
    3. Corners of buildings
  5. Remove Spider webs regularly
    1. Use brooms or vacuums
    2. Apply safe indoor Insecticides (Pyrethrins)
  6. Dress for working outdoors
    1. Keep skin covered by clothing
      1. Wear gloves
      2. Shirt tucked into pants
      3. Pants tucked into socks
      4. Wear a hat and high collar
      5. Avoid loose clothing
    2. Avoid Insect attractants
      1. Bright colors
      2. Perfumes
  7. Insect Repellents
    1. DEET
      1. Mosquitoes
      2. Fleas
      3. Gnats
      4. Chiggers
    2. Permethrin (Elimite, Nix) on clothes
      1. Ticks

Images: Related links to external sites (from Bing)

Related Studies

Ontology: Arachnidism (C0003705)

Concepts Injury or Poisoning (T037)
MSH D001098
ICD10 T63.3
SnomedCT 217665000, 330853007, 217669006, 367357009, 157929007, 65380003, 212881003
English Poisoning due to venomous spider NOS, Poisoning due to venomous spiders, Poisoning:venom-spider NOS, Poisoning:venom-spiders, Spider envenomation, Spider venom - toxic effect, Spider venom causing toxic effect, Toxic effect of venom of spider, Venom of spider, Arachnidism, Spider envenomation (disorder), Poisoning due to venomous spider NOS (disorder), Poisoning by venomous spider bite (disorder), Poisoning due to venomous spiders (disorder), Spider venom causing toxic effect (disorder), Poisoning by venomous spider bite, Spider venom causing toxic effect (event), arachnidism, araneism, Poisoning by venomous spider bite, NOS, Spider venom causing toxic effect [Ambiguous], Poisoning due to venomous spider NOS (finding), Poisoning due to venomous spiders (finding), Poisoning due to venomous spider (disorder), Poisoning due to venomous spider
Spanish envenenamiento por araña venenosa (trastorno), envenenamiento por araña venenosa, envenenamiento por picaduras de arañas (hallazgo), envenenamiento por picadura de venenosa, SAI (hallazgo), envenenamiento por picaduras de arañas, envenenamiento por picadura de venenosa, SAI, envenenamiento por picadura de venenosa, SAI (trastorno), intoxicación por picadura de araña, veneno de araña que causa efecto tóxico (trastorno), intoxicación por picadura de araña (trastorno), envenenamiento por la picadura de una araña venenosa, envenenamiento por la picadura de una araña venenosa (trastorno), veneno de araña que causa efecto tóxico, envenenamiento por picadura de araña, Aracnidismo
Swedish Araknidism
Finnish Araknidismi
German Toxische Wirkung: Spinnengift, Spinnengiftvergiftung
Japanese クモ毒症, クモ刺症, 毒グモ中毒, クモ刺咬症, クモ咬刺症, クモ咬傷
Korean 거미독액의 중독작용
Polish Ukąszenie przez pająka
Czech pavouci - kousnutí
French Arachnidisme, Aranéisme
Italian Aracnidismo
Norwegian Edderkoppforgiftning
Portuguese Aracnidismo
Dutch Gif van spin, Spinnenbeetziekte, Ziekte, spinnenbeet-

Ontology: Spiders (C0037913)

Definition (MSH) Arthropods of the class ARACHNIDA, order Araneae. Except for mites and ticks, spiders constitute the largest order of arachnids, with approximately 37,000 species having been described. The majority of spiders are harmless, although some species can be regarded as moderately harmful since their bites can lead to quite severe local symptoms. (From Barnes, Invertebrate Zoology, 5th ed, p508; Smith, Insects and Other Arthropods of Medical Importance, 1973, pp424-430)
Concepts Eukaryote (T204)
MSH D013112
SnomedCT 420814007, 23494002, 243674006, 359774004
English Spiders, Subclass: Araneae, Spider, Order Araneae (organism), Order Araneae, spiders, spider, Araneae, Spider (organism), Subclass: Araneae (organism), Spider, NOS, Spider [Ambiguous]
Spanish arañas, orden Araneae, orden Araneae (organismo), subclase: Araneae, araña, subclase: Araneae (organismo), araña (organismo), Araneae, Araneidos, Arañas
French Araignées
Swedish Spindlar
Czech pavouci
Finnish Hämähäkit
Croatian PAUCI
Polish Pająki
Norwegian Edderkopper
Portuguese Araneae, Araneidos, Aranhas
German Spinnen
Italian Ragni
Dutch Spin, Spinnen

Ontology: Spider Bites (C0242188)

Definition (MEDLINEPLUS)

Though many people are afraid of spiders, they rarely bite people unless threatened. Most spider bites are harmless. Occasionally, spider bites can cause allergic reactions. And bites by the venomous black widow and brown recluse spiders can be very dangerous to people.

If you are bitten by a spider, you may see a reaction similar to that of a bee sting, including redness, pain and swelling at the site. To treat a spider bite:

  • Wash the area well with soap and water
  • Apply an ice pack or a wet compress to the area
  • Take over-the-counter pain medicine, if needed
  • Consider using antihistamines for severe swelling
  • Seek medical treatment for small children and adults with severe symptoms

Definition (MSH) The effects, both local and systemic, caused by the bites of SPIDERS.
Concepts Injury or Poisoning (T037)
MSH D001098
English Bite, Spider, Bites, Spider, Spider bite, spider bite, bitten by spider (history), bitten by spider, Bite;spider, spider bites, Spider Bites, Spider Bite, Spider Bites [Disease/Finding], Spider bites, bite; spider, spider; bite
Dutch spinnenbeet, beet; spin, spin; beet, Spinnenbeet
French Morsure d'araignée, Morsures d'araignées
German Spinnenbiss, Spinnenbiß
Italian Morso di ragno, Morsicature di ragno
Portuguese Mordedura de aranha, Not Translated[Spider Bites]
Spanish Picadura de araña, Not Translated[Spider Bites]
Japanese くも咬傷, クモコウショウ
Czech Kousnutí pavoukem, kousnutí pavoukem
Hungarian Pókcsípés
Norwegian Edderkoppbitt