Page 39 - MNU-PM503 Parasitology practical book

Pharm D- Clinical Pharmacy Program Third Level Parasitology and virology (PM503)

2- Echinococcus granulosus

2- Egg:

a- Size: 30-50 u
b- Shape: spheroid with 2

envelopes:
- outer eggshell,
- Inner embryophore with two polar

thickenings from each arises 4-8 filaments.

c- Colour: translucent.

d- Contents: mature hexacanth
embryo.

Definitive host - Dogs, foxes and wolves.

Intermediate host - Sheep, cattle, goat, pigs and man

Reservoir host - No reservoir host

Infective stage - Hydatid cyst

Mode of infection - Dogs acquire infection by ingestion of hydatid

cyst in the viscera of herbivorous animals.
- In the small intestine of dogs the scolices
evaginates and develop into adult worms.

- Man and other herbivorous animals acquire
infection by ingestion of eggs with contaminated
food or vegetables.

Diagnostic stage - Eggs appear after 40-75 days in stool.

Site of localization - Small intestine of definitive host.

Diagnosis:

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