L 68 Ectoparasites Flashcards
Ticks are second to _____ in transmitting disease to humans
Mosquitos
Ticks are ______ feeders
Ticks are slow feeders and do not transmit disease quickly
What is the scutum and hypostome on the tick?
Scutum is the shield-like back
Hypostome is just above move, used for attachment
How to remove a tick
Grasp the tick with forceps near the head and gentle pull
Don’t squeeze the body!
Tick disease prevention
Wear long sleeves and pants
Check often for ticks and use deet
What are the ticks that cause Lyme Disease?
Ixodes
Amblyomma americanum
Which ticks cause babesiosis?
Ixodes
Rhipicephalus sanguineus
Which ticks can cause paralysis?
Dermacentor
Amblyomma americanum
Which ticks cause Rocky Mountain Spotted Fever?
Dermacentor
Amblyomma americanum
Rhipicephalus sanguineus
Which tick is the Lone Star Tick?
Amblyomma americanum
What is tick toxicosis?
Tick paralysis
Usually after days of tick feeding
Female saliva causes sonduction block
Fatalities from respiratory paralysis possible
Removing tick leads to resolution within hours
Pyemotes dermatitis
Type of mite
Straw and grain itch
May provoke allergic response
Demodex folliculorum
Mite Causes Demodiciosis Causes Demodex dermatitis Looks like acne Involves follicle, is pruritic Remember the vermiform shape of the mite
Eutrombicula
Mite causing chigger dermatitis
Larval mite with long hypostome like a sword
Usually attacks animals–red lesions on animals
In humans produces pruritis but does not burrow
Mite is gone, but leaves hypostome in skin causing itch
Just treat the itch
Scabies
Mite Sarcoptes scabiei A burrowing mite–female only, lays eggs Causes pruritic eruptions Can be an STD Dog version short lived Human type from crowded conditions
Norwegian Scabies
Crusted lesions teeming with mites
Head, neck, buttock, perianal
Assoc with HIV
Scabies diagnosis
Apply mineral oil to skin, scrape lesion and visualize microscopically
Whole or mite parts visualized
Scabies treatment
Permethrin
Ivermectin–anti-helminthic
Pruritis might continue
Lice species on head, body, pubic
Phthirus: pubic
Pediculus: head and body
Are lice a big deal?
Not really
Crabs?
Phthirus pubis or pubic lice
Nits (eggs) cemented to hair follicles, adults feed in pubic area
Transmitted by sexual contact
Pediculus humanus
Pediculosis is a type of lice that infects the head and body
Only the body louse is vector for epidemic typhus
Treated with permethrin
Transmitted in crowded conditions–don’t share clothes, combs
