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

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

Cantharidin Poisonous chemical secreted by the blister beetlePoisonous chemical secreted by the blister beetle

Dangerous Insects BitesBites StingsStings AllergiesAllergies DermatitisDermatitis MyiasisMyiasis Psychological DisordersPsychological Disorders Modes of Action

Dangerous Insects MortalityMortality –40 to 100 deaths annually in the U.S. Date Rate (per 1,000,000 people)Date Rate (per 1,000,000 people) –Stinging Insects0.20 –Alcohol related500 –Handgun related 85 –Lightning0.50 –Scholastic football0.12

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.

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.

Black Widow

Hobo Spider

Hobo spider bite – mildly venomous – often necrotic

Brown Recluse

Camel Spider – a Solipugid {not a real spider}

Venomous Hymenoptera Mass envenomationMass envenomation –LD 50 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??

Honey Bee Stinger

Hornet Stinger NO Barbs

Venomous Hymenoptera Ant VenomAnt Venom –family Formicidae offense-defense-communicationoffense-defense-communication Wasp VenomWasp Venom –multiple families prey capture - defenseprey capture - defense Bee VenomBee Venom –multiple families defense onlydefense only

Solenopsis invicta The Red Imported Fire Ant – Solenopsis invicta

Dangerous Hymenoptera Toxic vs. Allergic ResponseToxic vs. Allergic ResponseToxic –results from multiple stings –sometimes difficult to distinguish from an allergic response –Symptoms gastrointestinal dysfunctiongastrointestinal dysfunction faintingfainting muscle spasmsmuscle spasms convulsionsconvulsions et aliaet alia

Dangerous Hymenoptera Allergic ReactionAllergic 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!!!!Find Out!!!! Get treatment!!!!Get treatment!!!!

The Allergic Response NormalNormal {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.

The Allergic Response Large Local ReactionLarge 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.

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

ANAPHALAXIS CutaneousCutaneous –rashes-swelling-hives on various parts of the body VascularVascular –dizziness, fainting & unconsciousness RespiratoryRespiratory –difficulty breathing, constrictions in throat Misc.Misc. –chills, fever, anxiety, incontinence

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

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

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

ERUCISM Etymology –Latin ‘ eruca ’ = caterpillar Envenomation by toxic setae of caterpillars Hickory Tussock Moth caterpillarPuss moth caterpillar

ERUCISM Io Moth

ERUCISM Saddlebackcaterpillar A Saturnine moth common to the east side of Oregon Sibine stimuli

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

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

Rhodnius prolixus dining

Coleoptera Bombardier BeetlesBombardier Beetles –family Carabidae –When disturbed release a hot-toxic spray of quinones & H 2 O 2 at temperatures of 100° C.

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

Delusional Parasitosis Perceived to be “ infested ” with insectsPerceived 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 remediesUse of home remedies Self exposure to often dangerous levels of insecticides.Self exposure to often dangerous levels of insecticides.

Delusional Parasitosis SYMPTOMSSYMPTOMS –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 ”delivers or mails containers with “ bugs ” samples consist of anything but “ bugs ”samples consist of anything but “ bugs ” –self-mutilation can occur

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