Pest, Plagues & Politics Lecture 12 Dangerous Insects

1. Pest, Plagues & PoliticsLecture 12Dangerous Insects Yes, it is true!! Some insects can hurt you!!! Stinging Rose caterpillar

2. Key Points • Modes of Action • Venomous Hymenoptera • Wasp vs. Bee vs. Ant • Allergic vs. toxic response • Anaphylaxis • Other Families of dangerous insects • Psychological Aspects

3. Cantharidin • Poisonous chemical secreted by the blister beetle

4. Dangerous Insects Modes of Action • Bites • Stings • Allergies • Dermatitis • Myiasis • Psychological Disorders

5. Dangerous Insects • Mortality • 40 to 100 deaths annually in the U.S. • Date Rate (per 1,000,000 people) • Stinging Insects0.20 • Alcohol related 500 • Handgun related85 • Lightning 0.50 • Scholastic football0.12

6. Insects vs. Arachnids Arachnid venom can be toxic enough to kill with a single envenomation one bite = one death With insect venom, death is “usually” caused by an over reaction of the immune system.

7. Poisonous Spiders in Oregon • The black widow • The yellow (or gold) sac spider • The hobo spider (aggressive house spider) The brown recluse does not naturally occur in the PNW.

8. Black Widow

9. Hobo Spider

10. Hobo spider bite – mildly venomous – often necrotic

11. Brown Recluse

12. Camel Spider – a Solipugid {not a real spider}

13. Venomous Hymenoptera • Mass envenomation • LD50 of honey bee venom = 1,000 stings • Toxicity of honey bee venom  eastern diamond back rattle snake. • Who is going to stick around to get one thousand stings??

14. Honey Bee Stinger

15. Hornet Stinger NO Barbs

16. Venomous Hymenoptera • Ant Venom • family Formicidae • offense-defense-communication • Wasp Venom • multiple families • prey capture - defense • Bee Venom • multiple families • defense only

17. The Red Imported Fire Ant – Solenopsis invicta

19. Dangerous Hymenoptera • Toxic vs. Allergic Response Toxic • results from multiple stings • sometimes difficult to distinguish from an allergic response • Symptoms • gastrointestinal dysfunction • fainting • muscle spasms • convulsions • et alia

20. Dangerous Hymenoptera • Allergic Reaction • an altered sensitivity due to a previous exposure to the venom • 0.08% of the general population • Are You of this small minority?? • Find Out!!!! • Get treatment!!!!

21. The Allergic Response • Normal {note: everyone is allergic} • it hurts!! • Pain lasts a variable period • Accompanied by the appearance of a wheal • Soreness & itching which usually persists for 24 to 48 hours.

22. The Allergic Response • Large Local Reaction • swelling at the sting site & beyond over a 4 to 12 hour period • persists for more than 48 hours • soreness & itching can be severe • not Fun • but not overly serious from a medical standpoint.

24. The Allergic Response • Systemic Reaction • Deserves serious medical concern • Potentially life threatening • Body responds to the sting in areas far removed from envenomation site. • Anaphylaxis can result

25. ANAPHALAXIS • Cutaneous • rashes-swelling-hives on various parts of the body • Vascular • dizziness, fainting & unconsciousness • Respiratory • difficulty breathing, constrictions in throat • Misc. • chills, fever, anxiety, incontinence

26. ANAPHALAXIS • Medical Emergency • 58% of deaths occur within one hour of sting • 75% of deaths occur within six hours of sting • Treatment • EPINEPHRINE (adrenaline) • Causes vasoconstriction, which counteracts the vasodilatation properties of venom

27. Treatment • Currently two systems • ANA-KIT • EPIPEN • both are sub-epidermal injections of pre-measured doses of adrenaline • Requires a prescription to obtain • Oregon law allows persons other than physicians to administer.

28. Immunotherapy • Is all the trauma necessary?? NO!! • Desensitization is effective ca. 95% of the time.

29. ERUCISM • Etymology • Latin ‘eruca’ = caterpillar • Envenomation by toxic setae of caterpillars Puss moth caterpillar Hickory Tussock Moth caterpillar

30. ERUCISM Io Moth

31. ERUCISM Saddleback caterpillar Sibine stimuli A Saturnine moth common to the east side of Oregon

32. LEPIDOPTERISM • An allergic response triggered by the wing scales of any number of moths &/or butterflies. • Expressed by respiratory distress.

33. Hemiptera • Some formidable biters in several families • Assassin Bugs • family Reduviidae • Predaceous on other insects • utilize extra-oral digestions • enzymes injected into the food/prey item • a fine line between venom & digestive enzymes

34. Rhodnius prolixus dining

35. Coleoptera • Bombardier Beetles • family Carabidae • When disturbed release a hot-toxic spray of quinones & H2O2 at temperatures of 100° C.

36. Psychological Aspects • Entomophobia • a morbid, irrational fear of, or aversion to insects. • Most deeply manifested by the condition of delusional parasitosis

37. Delusional Parasitosis • Perceived to be “infested” with insects • in or under the skin • around or just inside body openings • in sputum • internally, particularly the stomach or intestines • in the vicinity of the sufferer, particularly in the home • Use of home remedies • Self exposure to often dangerous levels of insecticides.

38. Delusional Parasitosis • SYMPTOMS • a long time sufferer • seen by numerous physicians, exterminators, parasitologists, hygienists & entomologists • fiercely rejects negative findings • exhibits the “matchbox sign” • delivers or mails containers with “bugs” • samples consist of anything but “bugs” • self-mutilation can occur

39. Key Points • Modes of Action • Venomous Hymenoptera • Wasp vs. Bee vs. Ant • Allergic vs. toxic response • Anaphylaxis • Other Families of dangerous insects • Psychological Aspects