Jabberwocky The jaws that bite The claws that catch

1
JabberwockyThe jaws that biteThe claws that
catch

• Bites
• And the great outdoors
• Jim Giesen, M.D.

2
JabberwockyLewis CarrollTwas brillig, and the
slithey tovesDid gyre and gimble in the
wabeAll mimsy were the borogoves,
And the mome raths outgrabe.Beware the
Jabberwock, my son!The jaws that bite, the claws
that catch!Beware the Jubjub bird,
and shun the frumious
Bandersnatch!
3
Blood Sucking Arthropodsand the Joy They Bring Us
4
Mosquitoes

• Vector to more disease in humans than any other
  blood feeding arthropod
• Worldwide greater than 3 million deaths per year
  from malaria alone
• Mosquito transmitted disease will be responsible
  for the death of one out of seventeen people
  currently alive

5
Mosquito Borne Diseases

• Eastern and Western equine encephalitis
• St.Louis and La Crosse encephalitis
• West Nile Virus
• Malaria
• Dengue
• Bancroftian filariasis
• Epidemic polyarthritis
• Chikungunya fever
• Rift Valley fever

6
Mosquito Facts

• Only females suck blood(true Amazons)while wimpy
  males sip on nectar and plant juices
• Consume up to their own weight in blood every 3-4
  days
• Some species are zoophilic some anthropophilic
• and some switch hosts seasonally providing a
  means for transmitting disease from animals to
  humans

7
Mosquito Attractants

• Visual,thermal, and olfactory stimuli attract
  them
• Visual stimuli important for in flight
  orientation. Thermal and olfactory more important
  as the mosquito closes in
• Carbon dioxide and lactic acid are two well
  studied attractants
• Carbon dioxide can draw mosquitoes from as far
  away as 100 feet
• Volatile compounds, sweat, and fragrances from
  lotions, soaps, perfumes may be attractants
• Men preferred over women, adults over children,
  my wife over me

8
Blackflies

• Late Spring Early Summer scourge of the
  northwoods
• Mouthparts tear the skin surface and produce a
  pool of blood from which the fly feeds
• Rare systemic reactions-fever, urticaria, and
  rarely anaphylaxis
• Intensely pruritic, painful,and slow to heal
• Tropical species transmit Onchocerca volvulus-the
  parsitic cause of river blindness

9
Other Flies and Bugs

• Tabanids- horseflies, deerflies have been shown
  capable of transmittting tularemia
• Sandflies- Tiny flies associated with
  leishmaniasis
• Tsetse flies- African trypanosomiasis(sleeping
  sickness)
• Kissing bugs(Assassin bugs)- Vector for
  Trypanosoma cruzi the causative agent of Chagas
  disease
• Fleas- Plague and murine typhus
• Chigger mites-Pierce the skin with mouthparts and
  secrete a proteolytic saliva that dissolves host
  tissue creating a porridge which is then lapped
  up. Transmit scrub typhus

10
General Treatment of Insect Bites

• Oral antihistamines
• Ammonium solution 3.6 (After Bite) relieves
  Type1 hypersensitivity symptoms dramatically
• Watch for secondary infection

11
Ticks

• Most noted for high nuisance potential
• Efficient vectors for a large number of zoonoses
• In the US ticks outrank mosquitoes as vectors and
  tick-borne illnesses constitute an important
  infectious disease problem

12
Tick envenomation

• Ticks cause disease by either transmitting
  microorganisms or by secreting toxins or venoms
• Some trigger potent immune responses others have
  direct tissue toxicity
• Clinical effects range from localized reactions
  to anaphylaxis, paralysis, and death

13
Pajaroello Tick Bites

• Desert southwest,California, and Mexico
• Thought to be locally necrotizing toxin resulting
  in a 2-3 cm
• Local erythema, pain, and edema followed by
  tissue necrosis and ulceration
• Rare severe allergic reactions

14
Tick Paralysis

• First reported by Todd in 1912
• Acute ascending motor paralysis appearing similar
  to Guillan Barre, botulism,or myesthenia gravis
• 43 different species of tick have been implicated
  in the US and Australia
• Neurotoxic venom secreted from the tick salivary
  gland causes the paralysis

15
Clinical Features

• Paralysis develops 5-6 days after a female tick
  attaches, usually to the head or neck
• Restlessness, irritability, and paresthesias
  followed by ascending, symmetric flaccid
  paralysis
• Cerebellar dysfunction may occur with
  incoordination and ataxia
• Resolution of paralysis with tick removal
  establishes the diagnosis

16
Ticks as Vectors

• Lyme Disease
• Rocky Mountain Spotted Fever
• Relapsing Fever
• Colorado Tick Fever
• Ehrlichiosis
• Babesiosis
• Tularemia

17
Ehrlichiosis

• Two forms in humansHuman monocytic
  ehrlichiosis(HME) and human granulocytic
  ehrlichiosis(HGE)
• HME is transmitted by the Lone Star Tick and is
  found in the south and east
• HGE is found in the upper Midwest and Northeast.
  Range tends to overlap areas where Lyme disease
  is endemic
• 70 occur in May-July
• Broad clinical spectrum of disease from mild
  viral-like illness to life threatening
  neurological complications

18
Ehrlichiosis

• HGE only develops rash 10 of the time
• Caused by Ehrlichia equi like organism with
  reservoir hosts including sheep, deer, and
  rodents
• Confirm with serologic testing after initiating
  empiric therapy with doxycycline 100 mg BID for a
  minimum of 7-10 days

19
Prevention and Prophylaxis

• Prophylaxis not usually recommended. Even if tick
  is infected the risk of transmission is low if
  the tick is found and removed promptly
• Proper tick removal technique is imperative
• Proper clothing can help
• DEET containing sprays and lotions repel ticks.
  Use formulas containing less than 10 DEET for
  children
• Permanone is a tick repellant for use on clothing
  and its active ingredient permethrin kills ticks
  on contact. Field tests have shown permethrin to
  be 90 effective in preventing tick bites

20
Tick Pix
21
Case Report

• 20 year old intoxicated college student presented
  to Tucsons El Dorado Hospital ER with severe
  cramping back and leg pain. He had stumbled home
  and plopped himself naked into the bath tub. He
  woke up sometime later crying out with pain. His
  friend brought the patient and a flattened black
  spider to the ER

22
The Suspect
23
Widow Spiders

• Shiny black spider with characteristic red
  hourglass on the abdomen
• Latrodectus spiders are worldwide in their
  distribution and in the US occur in every state
  except Alaska
• Tend to bite defensively when accidentally crushed

24
Widow Spider Venom

• Potent mammalian neurotoxin which causes massive
  neurotransmitter release from presynaptic endings
• Latrodectism, the syndrome resulting from
  envenomation, is characterized by widespread
  sustained muscle contraction rather than for
  local tissue injury

25
Clinical Presentation

• Involuntary spasm of large muscle groups of
  abdomen, limbs, and lower back can appear within
  30-60 minutes of the envenomation
• Abdominal symptoms can mimic acute abdomen
• Associated signs may include fasciculations,
  weakness, ptosis, priapism, fever, salivation,
  diaphoresis, and bronchorrhea
• Symptoms may remain severe for several days. Care
  is largely supportive though an antivenin is
  available for life threatening cases
• Special care must be taken in pregnancy(premature
  labor) in severe hypertension and in children

26
Recluse Spiders
27
Recluse Envenomation

• Complex venom with at least 8 or 9 major protein
  bands
• Components are both dermonecrotic and directly
  hemolytic
• Clinical spectrum ranges from mild and transient
  skin irritation to severe local necrosis and
  dramatic hematologic and renal injury

28
Recluse Bites
29
Another Recluse Bite
30
Tarantula
31
Urticating Hairs

• Abdominal hairs which are barbed and may contain
  an irritant venom
• Type 1,2,3,and4 hairs cause varying degrees of
  inflammation
• Urticating hairs of Tarantulas can be transmitted
  hand to eye and are the cause of potentially
  severe ophthalmic injury

32
Wisconsin Venomous Reptile Bites

• A middle aged fly fisherman was working the banks
  of Black Earth Creek a couple of years ago. He
  felt a sharp pain in his lower leg. Over a period
  of several hours the pain intensified and the leg
  became red and swollen. A middle aged plastic
  surgeon with whom I shared a beer or two in
  medical school astutely noted the paired puncture
  wounds on the leg, measured the distance between
  the two punctures and arrived at the correct
  diagnosis.

33
Massasauga
34
Timber Rattlesnake
35
Field Treatment of Pit Viper Bites

• Little science and lots of anecdotal
  recommendations
• Weigh benefit against risk of treatment
• Severe envenomations require antivenom and all
  due haste should be made to get the victim to a
  site for definitive care
• Avoid mechanical suction devices
• Avoid tourniquets even simple veno occlusive band
  as they may make local tissue necrosis worse
• Recognize that defensive bites may be dry with
  little or no delivery of venom

36
Antivenom

• Antivenin(Crotalidae)Polyvalent is derived from
  horse serum
• Derived from horses immunized against two North
  American and one South American viper
• Can be used for treatment of bites by any North
  American pit viper
• Risk of acute reaction to antivenom itself.
  Should not be used in the field unless full
  resuscitative support is available
• Newer sheep derived and purified antivenom,
  CroFab has been approved by the FDA for mild to
  moderate envenomations

37
Other Bites and Issues

• Other envenomations and stings
• Mammalian Bites Local wound issues, microbiology
  of wound infections, tetanus and rabies
  prophylaxis
• Large animal attacks Bear, mountain lion, muskie
• Homo horribilus- drunk on a Saturday night

38
Twas brillig and the slithey tovesDid gyre and
gimble in the wabeAll mimsy were the
borogoves,And the mome raths outgrabe.The End