1. Ectoparasitic Disease

2. Ectoparasitic Disease
An ectoparasite is an organism that derives benefit or fulfills a life cycle requirement through interaction with the outer, or cutaneous, surface of the host.

3. Bed Bugs Order Hemiptera (true bugs) Family Cimicidae
Cimex lectularius (Human Bedbug)
Temperate climates
5 to 7 mm adults, 1.5 mm nymphs
Cimex hemipterus
Tropical climates.

4. Bed Bugs
They hide in cracks ad crevices with eggs hatching every 4 to 10 days.
Heavy infestations produce a pungent odor.
Usually bites at night on exposed areas of skin.
Attracted to warmth and CO2.
Has a complete blood meal in 5-10 minutes.
The bite is painless and anticoagulant is injected by the insect.

5. Bed Bugs May have several bites in a row.
Breakfast, Lunch, and Dinner.
Usually appears as a wheal with a central hemorrhagic punctum.
Have not been found to be competent vectors for disease.
Management of bedbug infestations start with identification of the bug and thus the primary host followed by calling pest control.

7. Lice The suborder Anoplura (Sucking Lice) Pediculosis Capitis
200 species
Pediculosis Capitis
Pediculus humanus var. capitis
Pediculosis Corporis
Pediculus humanus var. corporis
Pediculosis Pubis
Phthirus pubis

8. Pediculosis Capitis Female life span is 1 month and lays
7-10 eggs (nits) daily.
Eggs hatch in 8 days.
Can survive 55 hours without a host.
Lice do not jump, fly, or use pets as vectors.
Nits do fluoresce a pale blue under a woods lamp and are cemented securely to the hair shaft unlike dandruff.
Using a fine toothed nit comb is more efficient for detecting lice compared to visual inspection.

9. Pediculosis Capitis
Finding nits without lice does not mean active infection and may persist for months after successful therapy.
Many nits found ¼ inch from the scalp indicates active infection.

10. Pediculosis Capitis
Topical permethrin, pyrethrin, and malathion are all effective in more than 95% of cases.
Permethrin creams appear the least toxic to humans and are considered first line therapy despite emerging resistence.
CDC recommends a second treatment application in 7 to 10 days.
Lindane shampoo is not first line due to potential neurotoxicity and widespread resistance.

11. Pediculosis Capitis
Suffocating the Lice with oils or silicone based jellies, electrocuting them with electric combs, and high volume heated air blown on the scalp have been unproven treatments.
Household members should be examined and treated if infested with bunkmates treated prophylactically.

12. Pediculosis Corporis
Largely a problem of the homeless and is a reflection of personal hygiene.
Associated diseases
Louse-borne typhus
Rickettsia prowazekii
Trench fever
Bartonella quintana
Relapsing fever
Borrelia recurrentis

13. Pediculosis Corporis Itching is the chief complaint.
The patient should be bathed thoroughly with infested clothing and bed linen heat washed and dry cleaned, or discarded.
Can live as long as 30 days away from the host.
May use topical insecticides if nits are found.

14. Pediculosis Pubis
Most crab lice infestations in young adults result from sexual contact.
Itching is the chief complaint, usually involving the pubic area or axillae but may involve body hair excluding the scalp.
In children the eyelashes (pediculosis ciliaris) may be involved.
Should screen for other STD’s

15. Pediculosis Pubis Treatment Treat all contacts at the same time.
Permethrin 1% cream or Pyrethrins with piperonyl butoxide applied to affected areas and washed off after 10 minutes.
Malathion 0.5% lotion applied to affected areas and washed off after 8-12hours.
Ivermectin 250mcg/kg orally, repeat in 2 weeks.
Treat all contacts at the same time.

16. Mites From the Order Acarina and class Arachnida.
Only Scabies and Demodex (Follicle mites) parasitize humans.
Mites that affect humans which do not burrow into human skin.
Chiggers
Animal Mites
Food, Grain, and Straw Mites
Follicle Mites

17. Chiggers The harvest mite or red bug.
Family Trombiculidae
Lives on grass and shrubs and is prevent in the southern U.S.
The larva attaches itself to passing animals or humans, feeds then drops off.
Hours later an extremely pruritic, erythematous papule appears.
Chiggers are vectors for:
Scrub Typhus in southeastern Asia
Orientia tsutsugamushi

18. Follicle Mites Demodex folliculorum Demodex brevis
Mites which inhabit the pilosebaceous follicles, especially the face and eyelids of humans and some animals.
Usually considered harmless saphrophytes.

19. Scabies Sarcoptes scabiei var. hominis
300 million people affected worldwide.
Can occur in epidemics.
More common in temporate climates and in the winter.
Transmission of scabies is from direct contact.
Children get it from there mothers.
Adults usually get it through sexual contact.
The mites can survive off of there host for hours but can survive much longer in colder conditions with relatively high humidity.

20. Scabies
Once fertilized the female burrows into the epidermis where it lays up to eggs over a month before dying.
The eggs hatch in 3 to 4 days and molt three times before leaving the burrow.
Symptoms usually appear 3-4 weeks after the primary infection with itching and redness as a reaction to the eggs and feces.

21. Scabies

22. Crusted Scabies or Norwegian Scabies
Occurs in patients with compromised cellular immunity such as AIDS, Leprosy, or Lymphoma.
Because of the lack of cellular immunity the skin becomes crusted with hundred of thousand of mites.
Itching maybe minimal or absent.

23. Scabies
Confirmation of infection can sometime be done by finding the mite or eggs in scrapings from burrows or papules.
Treatment usually includes topical Permethrin or oral Ivermectin.
Treat all close contacts at the same time.
Would wash clothes and linens as well.

24. Ticks 899 species in the world. 90 species in the US
80 ssp. in the Family Ixodidae “HardTicks”
10 ssp. in the Family Argasidae “ Soft Ticks”

25. Ticks The Differences Between Hard Ticks And Soft Ticks?
Feature Hard Tick Soft Tick
Scutum (dorsal shield) present not present
Capitulum (mouth parts) anterior ventral
visible from above not visible from above
Nymphal stages one several
Adult feeding time several days min.
Female blood meals one several
Egg laying events one several
Total eggs laid 3,000-8,

26. Typical Life Cycle of a Hard Tick

27. Amblyomma americanum The Lone Star Tick
Southeastern and South-central U.S
Hosts include ground-dwelling birds, small mammals, and large mammals such as deer, livestock, humans, and pets
Diseases
Tularemia
Human Monocytic Ehrlichiosis
Southern tick-associated rash illness (STARI)
Borrelia lonestari

28. Ambylomma maculatum The Gulf Coast Tick Diseases
None (but bites aggressively)

29. Dermacentor variabilis
The American Dog Tick
Eastern U.S., in Colorado, and the Pacific Northwest
Larvae and nymphs feed on small mammals, especially meadow mice.
Adults feed on deer and other wild animals, livestock, pets, and humans.
Diseases
RMSF (Primary Vector)
Tick paralysis
Tularemia
Anaplasmosis

30. Ixodes scapularis The Black-legged Tick Eastern U.S.
Larvae feed primarily on white-footed mice.
Nymphs feed primarily on bird, lizards, small mammals, humans, and pets.
Adults feed readily on deer.
Diseases
Lyme Disease (primary vector)
Human Granulocytic Ehrlichiosis (Anaplasmosis)
Babesiosis
Ixodes pacificus (Western Black-legged Tick) transmits Lyme disease on the west coast.

31. Rhipicephalus sanguineus
The Brown Dog Tick
Southern U.S.
Dogs are the primary host for larvae, nymphs, and adults.
Diseases
Possibly RMSF

32. Demacentor andersoni The Rocky Mountain Wood Tick
Rocky Mountains and adjacent areas.
Diseases
RMSF
Colorado Tick Fever
Tularemia
Tick Paralysis

33. Ornithodoros hermsi and Ornithodoros turicata
The Relapsing Fever Tick
Western, Southwestern, and South Central U.S.
Mainly feed on rodents.
Disease
Relapsing fever

34. How to remove a tick.

35. The End

36. Myiasis

37. Tungiasis