1. Medical Entomology

2. MEDICAL IMPORTANCE OF ARTHROPODS
1)As aetiologic agents (causes) of diseases.
Tissue damage
Induction of hypersensitivity reactions.
Injection of poisons
Entomophobia (acarophobia)
2) As vectors of diseases:
I: Mechanical transmission - simple carriage of pathogens.
II: Biological transmission:
- cyclical
- propagative
- cyclopropagative
III: Transovarian transmission

6. Scabies
Scabies

7. Scabies

8. Scabies

9. Scabies

10. Scabies

11. Scabies

12. Scabies

13. Scabies

14. Scabies

15. Scabies

16. LICE
Pediculus humanus humanus (P.h.corporis): body louse
Pediculus h. capitis:head louse
Morphology: 2-3mm long
dorsoventrally flattened
Life Cycle : Head or body lice transferred by contact with infested person or clothes . Females deposit eggs on the hair (nits)Eggs hatch after 10 days -----nymphs maturation in 2 wks . Larvae and adults feed on human blood.
Diagnosis: nits are visible by naked eye , they fluoresce under UV light (Wood’s lamp for screening).
Pathology: Pedicolosis ,irritation and pruritus.
Body louse is vector for Relpsing fever, Typhus & Trench fever.

17. LICE
Louse(singular) , Lice (pleural)
Pediculus humanus

18. Pediculus humanus

19. The American Heritage® Dictionary of the English Language :
lousy (louzy)
adj. lous·i·er, lous·i·est ,lousi·ly adv. ,lousi·ness n.
1. Infested with lice.
2. Extremely contemptible; nasty: a lousy trick.
3. Very painful or unpleasant: a lousy headache.
4. Inferior or worthless: a lousy play.

20. Life cycle of the head louse
( Pediculus humanus capitis )

21. Nits of Pediculus humanus

22. Phthirus pubis Phthirus pubis (pubic louse or crab louse)
Smaller than Pediculus. (about2 mm)
Infests pubic hair mainly.
Transmitted by direct contact with infested person or clothes.
Life cycle days.Irritant , no disease transmission.

23. Phthirus pubis

24. Treatment of Lice infestation;
Removal and decontamination of clotheses 50 C, dry cleaning
Application of preparations containing permethrin
Removal of nits by fine comb

26. Myiasis ((التدويد

27. Myasis: summary
Caused by a large number of flies. Common in rural areas where people are in close contact with animals.
Eggs or first stage larvae are deposited on body apertures, wounds or introduced into unbroken skin. Larvae develop causing tissue damage.
Pathology and Clinical picture: depends on type of fly, location in body and number of maggots. Skin ulcer, aural, nasal or eye lesions.
Diagnosis: by identification of maggot.
Treatment: surgical removal.

28. Myiasis Classification:
Obligatory : larvae normally develop within or on living tissues of vertebrates e.g.:
Nasopharyngeal (i.e., relating to or affecting nose and pharynx) cavities of herbivorous mammals,
Cutaneous and subcutaneous tissues,
Facultative :larvae developing in decomposing organic materials or the necrotic tissues of living animals

29. Ophthamomyiasis

30. Myiasis
- Larva of human botfly, Dermatobia hominis, manually expressed from furuncle

31. Bed bugs
(Cimex lectularius)

32. Bed bugs (Cimex lectularius)
Bed Bug, small, flat, oval bloodsucking insect, with a reddish-brown color, reduced wings, and an unpleasant odor.
The common bed bug infests houses, particularly beds. It hides during the day and feeds at night, sucking the blood of humans and other mammals. Two to four generations are produced yearly, depending on the temperature and the food supply.

35. Bed bugs (Cimex lectularius)

36. Scorpions Highly venomous
Thick-tail scorpions (family Buthidae). They have thick tails and thin pincers.

37. Scorpions Non-venomous
Thin-tail scorpions (families Scorpionidae, Ischnuridae). They have thin tails and broad, well developed pincers.

38. Scorpions Local scorpions in KSA include :
The yellow scorpions (Leiurus quinquestriatus),
The black scorpion (Androctonus crassicauda).

39. This is a preparation containing the F(ab')2 fraction of the immunoglobulins raised against scorpion venoms. The antivenom is prepared by hyperimmunizing healthy horses using gradually increasing doses of local scorpion venoms and immunomodulators .

40. Bee stings
BEES 
Venoms of bees are a mixture of enzymes and several polypeptides some of which are pharmacologically active e.g. histamine or neurotoxic. Some people are hypersensitive to venoms and suffer anaphylactic reaction , death might result in 1 hour.

42. Latrodectus hasseltii (The Red-back Spider):
This spider is commonly found outdoors and around human habitation. It's often called The Red-back spider.
A bite from a hasseltii is highly venomous.
Hobo or Brown Recluse Spider:
A venomous bite from a can cause severe necrotic arachnidism results from envenomation (venom poisoning). It occurs due to the venom's ability to clot blood that results in an area of tissue receiving inadequate blood flow and thus dying secondary to oxygen starvation.

43. Important arthropod vectors for human diseases
House fly (Musca domestica)
Mechanical transmission of many viruses, bacteria and parasites.
Mosquitoes البعوض
Anopheles :malaria filariasis Culex: filariasis, viruses Aedes: yellow fever, dengue fever, Rift Valley Fever
Lice القمل
Body louse: vector for: Relapsing fever, typhus and trench fever.
Fleas البراغيث
Rat flea is vector for plague due to Yersinia pestis.
Ticks القراد
Soft ticks , some are vestors for : Borrela duttoni Hard ticks Include vectors for Babesiosis (protozoa), Q fever, and Rocky mountain spotted fever :
Tse tse fly (Glossina) ذبابة التسي
Vector for African Trynanosomiasis (African sleeping sickness)
Black fly (Simulium)الذبابة السوداء
Vector for Onchocerca (river blindness)
Sand fly (Phlebotomus) ذبابة الرمل
Vectors for leishmania and sandfly fever virus.
Cyclops
Vector for Dracunculus medinensis

44. HOUSE FLY
Musca domestica
World-wide distribution
Body with 3 visible parts,
3 pairs of legs
1 pair of visible wings.
Retracted mouth parts
Breeds in soil and dirt
Not a blood sucker.
Mechanical transmission of many diseases : viruses, bacteria and parasites

45. Mosquitoes : Cosmopolitan , more than 3000 species.
Larval and pupal stages always aquatic
Mouth parts in female adapted to piercing and sucking blood.
Genus and species distinguished by morphology of adult and deveopmetal stages.

46. Anopheles stephensi

47. Phlebotomus ( sand fly

48. Phlebotomus ( sand fly

49. Simulium damnosum (black fly)
Vector of Onchocerciasis ( river blindness)
Black in colour with hump back and short strong legs.
Short antennae and short strong mouth parts.
Breed in fast running stream of water , rich in Oxygen .
Diurnal activity.
Vector of river blindness (onchocerciasis).

50. Tse tse fly (Glossina spp)
Breeds in forests of central Africa.
Body with 3 visible parts,
3 pairs of legs
1 pair of visible wings.
Mouth parts well developed
for sucking blood.
Vector of African sleeping sickness.

51. Cyclops : vector for Dracunculus medinensis

52. Fleas
Wingless ,brown, laterally flattened, 3 pairs of well developed legs for jumping
Diseases:
Xenopsylla cheopis- rat flea:plgue, murine typhus.
Pulex irritans :
Rat flea

53. Fleas
Rat flea

54. TICKS
Body 1 segment
4 pairs of legs
no antennae
no wings
Soft ticks:
Vector for:
Relapsing fever
Hard Ticks:
Vector for:
Babesiosis,
Q fever, Rocky Mountain spotted fever

56. Brown Dog Ticks
A. Engorged Female
B. Female
C. Male
Black-Legged Ticks (Deer Ticks)
D. Larvae
E. Nymphs
F. Males
G. Females
H. Engorged Female

57. Triatomid bug , vector of Chagas disease ( American trypanosomiasis)