1. Eukaryotic Parasites (Protozoa) Drs. Babcock and Hopkins Spring 2009

2. Entamoeba histolytica (amebiasis, severe diarrhea)
Acquired through
consumption of
contaminated food
or water.
Trophozoite is feeding and
reproducing stage and causes
disease. Cyst is circular and
is what is ingested. Trophozoite
forms pseudopodia.
Target nuclei in both.

4. Entamoeba Histolytica trophozoites

5. Entamoeba histolytica cysts

6. Entamoeba histolytica with ingested erythrocytes

7. Balantidium coli (balantidiasis) Trophozoite has cilia. Cyst
does not. Large nucleus.
Can cause diarrhea and in severe
cases ulcers and abscesses that
can lead to dysentery and death.

8. Balantidium coli

9. Balantidium coli trophozoites

10. Balantidium coli trophozoites

11. Giardia intestinalis - giardiasis
2 nuclei
Flagella on
Trophozoite.

12. Giardia intestinalis - trophozoite

13. Giardia intestinalis trophozoite

14. Giardia intestinalis trophozoite

15. Trichomonas vaginalis life cycle
Single nucleus
Flagella. NO
CYST form.
Vaginitis with
malodorous discharge
and pruritis.

16. Trichomonas vaginalis trophozoite

17. Trichomonas vaginalis trophozoite

18. Trypanosoma brucei Flagellated. Seen in blood Smear outside of RBCs.
Tsetse fly
Arthropod vector,
Tsetse fly. Infection
through bite and
causes African
Sleeping Sickness.

19. Trypanosoma brucei

20. Plasmodium falciparum
Seen in blood smear inside RBCs.
Undergoes schizogony.
Causes Malaria
Arthropod vector
- Anopheles is vector

21. Plasmodium falciparum
Plasmodium vivax
Plasmodium ovale
Plasmodium malariae

22. Plasmodium falciparum “blackwater fever”

23. Toxoplasma gondii Produce toxoplasmosis
iIn humans when cysts ingested.
transplacental transfer can
occur.

24. Toxoplasma gondii

25. Toxoplasma gondii

26. Eukaryotic Parasites The Helminths Cestodes = Tapeworms Trematodes = Flukes Nematodes = Roundworms

27. Ascaris lumbricoides life cycle
Roundworm, dioecious.
Both male and female worms.

28. Ascaris lumbricoides (nematode)

29. Ascaris lumbricoides eggs in fecal smear

30. Ascaris lumbricoides

31. Clonorchis sinensis life cycle (Oriental liver fluke-Trematode)
Metacercariae are
cystlike and dormant
and ingested. Maturation
occurs in small
Intestine.
Snail, intermediate host

32. Clonorchis sinensis worm

33. Clonorchis sinensis worm
Monoecious, have both male
and female sex organs.

34. Clonorchis sinensis eggs

35. Dipylidium caninum: Cestode, tapeworm, monoecious.

36. Dipylidium caninum – eggs (eggball)

37. Dipylidium caninum eggs

38. Dipylidium caninum scolex and proglottids strobilia, immature, mature and gravid.

39. Echinococcus granulosus – hydatid cysts
tapeworm. Small, only 3 proglottids. Hydatid sand, cysts in infected tissue.

40. Echinococcus granulosus worm and eggs
Hooks on eggs for attachment

41. Echinococcus granulosus worm and eggs

42. Encysted scolices of Echinococcus granulosus in lung ("hydatid sand“)

43. Enterobius vermicularis (pinworm)
Nematode, dioecious

44. Enterobius vermicularis (pinworm)

45. Enterobius vermicularis eggs

46. Enterobius vermicularis worms

47. Ancylostoma (hookworm), nematode.

48. Ancylostoma (hookworm)

49. Ancylostoma (hookworm)
Burrows through skin, enters bloodstream and travels to lungs. Swallowed and
Establishes in intestine. Attaches and consumes host blood.

50. Ancylostoma eggs

51. Paragonimus westermani life cycle
Fluke, lung- Trematode, snail is intermediate host.

52. Paragonimus westermani lung fluke
monoecious
egg

53. Shistosoma mansoni (blood fluke) life cycle

54. Shistosoma mansoni (blood fluke) schistosomiasis

55. Schistosoma mansoni copulating pair

56. Schistosoma spp. eggs Schistosoma haematobium Schistosoma mansoni
Spike or spine on egg for attachment
Schistosoma haematobium
Schistosoma mansoni

57. Strongyloides stercoralis life cycle

58. Strongyloides stercoralis adult and egg

59. Taenia solium life cycle, pig tapeworm

60. Taenia solium scolex

61. Taenia solium eggs
Taenia solium

62. Wuchereria bancrofti life cycle

63. Wuchereria bancrofti microfilariae in blood smear

64. Wuchereria bancrofti - Elephantiasis

65. The End