Spiders, Spiders Everywhere

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Spiders, Spiders Everywhere
Theres a new venomous spider to watch out for!
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Case Report 1
http//pep.wsu.edu/pdf/PLS116_1.pdf

• 56 year old woman feels bite on thigh
• Nausea, migraine-like headache
• In few days, necrotic tissue sloughs off
• 2 weeks later she seeks medical attention
• Bleeding from nose, ears, etc.

Information taken from an article written by
Gordon Grice, September 2005, Bite of the Hobo
SpiderIs it arachnophobia or are people dying?
DISCOVER Vol. 26 No. 09.
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Was it a spider that made her sick?

• Darwin Vest, toxinologist
• The first to investigate the cause of the
  lesions.
• He collected spiders from houses where humans had
  developed lesions or had symptoms similar to the
  woman who died.
• He collected the venom and placed it on the backs
  of rabbits.

Hobo spiders could, in fact, cause necrotic
lesions.
The rabbits developed lesions just like those he
had seen on humans.
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Prime Suspect
http//pep.wsu.edu/pdf/PLS116_1.pdf

• Hobo Spider
• Genus, species Tegenaria agrestis
• Family Agelenidae
• Nicknamed mat weaver
• Common in Europe, entered US in the 1930s,
  attached egg sacs to shipments

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Hobo Spider
Symptoms Blistering wound ringed with yellow
(moon in a halo of smog) Headaches Disturbed
thinking (rare)
http//pep.wsu.edu/pdf/PLS116_1.pdf
Image of a finger with a wound caused by the
Hobo spiderOUCH!!
http//egov.oregon.gov/ODA/PLANT/ippm_spider.shtml
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Giant House Spider
HELPFUL to humans The Hobo spiders cousin Preys
on the Hobo spider
http//www.washington.edu/burkemuseum/spidermyth/m
yths/insidewolf.html
LARGE HAIRY SPIDER DOES NOT EQUAL WOLF SPIDER GHS
commonly mistaken for a Wolf spider. Classificatio
n based on arrangement of eyes.
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Yellow Sac Spider
Symptoms Stinging sensation Red sores with white
pustules Bite may blister and break May feel
mildly sick
http//lancaster.unl.edu/enviro/pest/Articles/Yell
owSacSpiders.htm
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Mexican Red Knee Tarantula
Symptoms Venom is relatively harmless to
humans. The bite is similar to a bee or wasp
sting. If their hairs poke your skin, they can
cause a rash, redness and itchiness. Allergic
reactions are unusual.
http//www.museum.vic.gov.au/spidersparlour/tarant
2.htm
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White-tailed Spider
Symptoms Burning pain Swelling Itchiness
http//www.usq.edu.au/spider/find/spiders/507.htm
4 days after bite http//www.avru.unimelb.edu.au/a
vruweb/wtspage.htm
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Black Widow
Symptoms Painful bite Painful rigid
abdomen Severe diffuse muscle pain Excessive
salivation Sweating Nausea/vomiting Difficulty
breathing Headaches Weakness
Symptoms Painful bite Painful rigid
abdomen Severe diffuse muscle pain Excessive
salivation Sweating Nausea/vomiting Difficulty
breathing Headaches Weakness
http//muextension.missouri.edu/explore/wildthing/
images/blackwidow.jpg
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Brown Recluse
Symptoms Necrotic lesions Dizziness Fever Chills
Rash Vomiting
http//www.uky.edu/Agriculture/Entomology/entfacts
/struct/ef631.htm
Spider bite
Bacterial Infection
http//www.uky.edu/Agriculture/Entomology/entfacts
/struct/ef631.htm
http//www.lib.uiowa.edu/hardin/md/brownrecluse.ht
ml
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Where Do They Call Home?
Map adapted from the following website http//www
.uky.edu/Agriculture/Entomology/entfacts/struct/ef
631.htm
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Where Do They Call Home?
Map adapted from the following website http//www
.uky.edu/Agriculture/Entomology/entfacts/struct/ef
631.htm
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What are the most dangerous spiders in the world?
Redback Spider
Black Widows
Redback spider http//faunanet.gov.au/wos/factfile
.cfm?Fact_ID82 Black Widow http//muextension.mis
souri.edu/explore/wildthing/images/blackwidow.jpg
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What are the most dangerous spiders in the world?
Funnel-web spiders
Funnel-Web Spiders http//www.avru.unimelb.edu.au/
avruweb/Fws.htm
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What are the most dangerous spiders in the world?
Recluse Spiders
Brown Recluse http//www.uky.edu/Agriculture/Entom
ology/entfacts/struct/ef631.htm
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What are the most dangerous spiders in the world?
Banana Spiders
Banana Spider http//www.rochedalss.qld.edu.au/wan
dering.htm
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Are daddy long legs the deadliest spider?
Nah, that is a myth! This myth may have been
started because daddy long legs actually prey one
of the more dangerous spiders, the Australian
Redback Spider.
http//spiders.ucr.edu/images/holplu1.jpeg
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How should you protect yourself?

• Shake out clothes and shoes before putting them
  on.

• Inspect bedding (sheets/pillow cases) before
  using.

• Bedspreads and bedskirts are potential risks
  contact with the floor.

• Be careful around woodpiles, rock piles, etc.

• Pesticides should be a last resort or if there is
  a heavy infestation.

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Questions?

• Why is it difficult for a doctor to correctly
  diagnose spider bites?
• Why do you think it would be unwise to use
  pesticides for spider control?

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Questions?

• Why is it difficult for a doctor to correctly
  diagnose spider bites?
• They oftentimes look like another disease such as
  a rash, bacterial infection, or even diseases
  like diabetes.
• Why do you think it would be unwise to use
  pesticides for spider control?
• You kill not only the bad spiders, but you also
  take out a natural predator of the bad spider
  (wolf spiders, giant house spiders do a great job
  of keeping insect populations and spider
  populations in check.