1. Lab(4)
Practical Parasites
The second stage
Assistant Lecturer
Muna Hashim
2014

2. Parasites are divided into three main phylum:
1.Protozoa Helminths Arthropods
Protozoa divided into three classes
Apicomplexa
Ciliophora
Sarcomastigophora

3. Platyhelminthes Nemathelminthes
Phylum : Helminthes
Class:
Platyhelminthes Nemathelminthes
Cestoda Trematoda Nematoda
Entrobuis vermicularis
and
Ascaris lumbricoides
Taenia sp. and
Echinococcus granulosis
Schistosoma sp.

4. Enterobius vermicularis
NEMATODES
Ascaris lumbricoides
Enterobius vermicularis

5. Ascaris lumbricoides

6. Common name:- Giant Intestinal round worms.
Disease:-Ascariaisis
Host :- The human is intermediate and final host.
Location in Definitive host :-
the adult worm: in small intestines .
larva: in lung .
Infective stage :- Ovum

7. Ascaris Lumbricoides female
Characteristics
200 –350 mm X 4- 6 mm
Ivory mixed light red
Straight
Absent
1.Size
2.Color
3.Posterior end
4. Spicules
5.Papillae
Ascaris Lumbricoides female

8. Male Characteristics 150 – 200 X 2 -4 mm Reddish pink Curved
Has two spicules
Has many from papillae
1.Size
2.Color
3.Posterior end
4. Spicules
5.Papillae
Ascaris Lumbricoides
male

9. Ascaris Worms in Intestine9

10. Round worms

11. The Eggs
Eggs
Unfertilized
Fertilized
Corticated
Decorticated

12. Fertilized egg( corticated egg)
1.Size: mm by mm.
2.Shape:-Rounded or oval
3. Shell:-Thick,consisting of 3 layers : (Inner layer ) consist of
thin yolk Membrane ,(Mid layer) thick ,(Outer
layer ) coarse consist of regular Albuminous,There is
crescent shaped clear space at the each end inside the
shell.
4.Colour:-Golden brown.

13. ( outer layer) coarse
( regular Albuminous )
(Inner layer)
the thin yolk membrane
( mid layer) thick
Embryo
Crescent space

14. Decorticated Egg
fertilized eggs sometimes may lack the outer albuminous layer and are colorless.

15. Unfertilized eggs : elongated and larger than fertile egg
1.Size: mm by mm.
2.Shape:- Elongated oval
3.Shell:-Thin ,not has inner layer , irregular
albuminous layer , not has Crescent space.

16. Modes of transmission
Occurs mainly by ingestion of contaminated food or water with eggs.
Occasionally by inhalation of contaminated dust
with eggs.
Children playing in contaminated soil may
acquire the parasite from their hands.

17. Diagnosis The diagnosis depends on the Identify worm or egg:-
The Stool examination : for seeing the adult worm or egg .
The sputum examination :for seeing larva during migration in the lung.
Eosinophilia as indicator on parasitic infection .

18. Ascaris lumbricoides life cycle of
280
Ascaris lumbricoides life cycle of

19. Enterobius vermicularis

20. Known name:- pin worm
Disease:- Enterobiaisis
Host :- human is intermediate and final host.
Location in Definitive host :
The adult worms inhabit in the cecum and the
colon.
Infective stage :- Ovum

21. Morphology Enterobius vermicularis Adult Male
1 to 4 mm long and has the posterior end curved strongly and has a single spicule .

22. Enterobius vermicularis Adult Female
8 to 13 mm in long , the posterior end extends like thread, not
has spicule .

23. Egg Size:-50 to 60 by 20 to 30 µm Color:- Colorless
Shape:- like letter (D) flat of one side and convex of another side
Shell:- Thick double wall .
Thick,Double walled shell
Developing embryo

24. Enterobius vermicularis
Ascaris
Enterobius vermicularis
Anal smear showing large numbers of Enterobius eggs under the lower power. In the background are also two Ascaris eggs.

25. Air inhalation that contaminated with eggs.
Mode of transmission
Ingestion of contaminated food or water with eggs
Air inhalation that contaminated with eggs.
Self-infection may also occur if transfer the eggs to themouth by fingers that have scratched the perianal area.

26. Diagnosis
Diagnosis are often clinically by observing the female worm (or many worms) in the perianal region, but can also be using the "scotch-tape" test, or swab of stool.