Parasites are divided into three main phylum:

1.Protozoa 2.Helminths 3.Arthropods

Protozoa divided into three classes

Apicomplexa

Sarcomastigophora

Ciliophora

Phylum : Helminthes

Class:

Platyhelminthes

Nemathelminthes

Cestoda Trematoda

Nematoda

Taenia sp. and Echinococcus granulosis

Schistosoma sp. Entrobuis vermicularis and Ascaris lumbricoides

NEMATODES

Ascaris lumbricoides

Enterobius vermicularis

Ascaris lumbricoides

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

Characteristics Female

1.Size

2.Color

3.Posterior end

4. Spicules

5.Papillae

200 –350 mm X 4- 6 mm

Ivory mixed light red

Straight

Absent

Absent

Ascaris Lumbricoides female

Characteristics Male

1.Size

2.Color

3.Posterior end

4. Spicules

5.Papillae

150 – 200 X 2 -4 mm

Reddish pink

Curved

Has two spicules

Has many from papillae

Ascaris Lumbricoides

male

Ascaris Worms in Intestine

Round worms

The Eggs

Eggs

Fertilized

Unfertilized

Decorticated

Corticated

Fertilized egg( corticated egg)

1.Size:- 45-75 mm by 35-50 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.

( outer layer) coarse

( regular Albuminous )

(Inner layer)

the thin yolk membrane

( mid layer) thick

Embryo

Crescent space

Decorticated Egg fertilized eggs sometimes

may lack the outer

albuminous layer and

are colorless.

Unfertilized eggs : elongated and larger than fertile egg

1.Size:- 85-95 mm by 43-47 mm.

2.Shape:- Elongated oval

3.Shell:-Thin ,not has inner layer , irregular

albuminous layer , not has Crescent space.

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.

DiagnosisThe 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 .

Ascaris lumbricoides life cycle of 280

Enterobius vermicularis

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

1 to 4 mm long and has the posterior end curved

strongly and has a single spicule .

Morphology Enterobius vermicularis Adult Male

8 to 13 mm in long , the posterior end extends like thread, not

has spicule .

Enterobius vermicularis Adult Female

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 .

Egg

Developing embryo

Thick,Double walled shell

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

Enterobius vermicularis

Ascaris

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.

Mode of transmission

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.

Diagnosis