1. 3- Blood Fluke Schistosoma sp.
Schistosoma mansoni male
Schistosoma mansoni female
Schistosoma mansoni male & female
Schistosoma haematobium male
Schistosoma haematobium female
Eggs of Schistosoma mansoni
Eggs of Schistosoma haematobium
Snail of Schistosoma mansoni
Snail of Schistosoma haematobium
S. mansoni cercaria

2. S. mansoni (male & female)
Schistosoma mansoni
S. mansoni (male)
8-10 mm long
has gynaecophoric canal
dorsal surface covered with tubercle
S. mansoni (female)
14 mm long
taller and thinner
vitelline glands occupy 2/3 of the body
S. mansoni (male & female)

3. S. mansoni (snail) Biomphalaria alexandrina
S. mansoni (egg)
oval with lateral spine
Cercaria of S. mansoni
elongated head
biforked tail

4. Schistosoma haematobium
Egg
oval with terminal spine
Snail
Bulinus truncatus

5. veins of urinary bladder (venous plexus of urinary bladder)
S. haematobium
S. mansoni
veins of urinary bladder (venous plexus of urinary bladder)
veins of large intestine, colon (lower mesentric vein)
Location
Bulinus truncatus
Biomphalaria alexandrina
Intermediate host
Eggs in urine
Eggs in stool
Diagnosis
Cercariae
Infective stage
Direct skin penetration of cercariae during swimming
Mode of transmission
Urinary Bilharziasis
Intestinal Bilharziasis
Disease

6. Class Cestoda

7. General Characters Tape Worms
1- All worms have long flat (no body cavity), multi-segmented body.
2- The body is covered with cuticle that is provided with pores through which the worm uptakes its nutrients (no digestive system).
3- All are hermaphrodites (each segment contains both male and female sexual organs).

8. 4- The adult worm is divided into 3 distinct parts:
a- Head or Scolex: usually with 4
muscular suckers and a crown
of hooks (rostellum) to attach to the
intestinal wall.
b- Neck Region: serves as a
generative organ
c- Strobilla: three types of segments
(Proglottids).
i. Immature: following the neck region
ii. Mature: containing both sex organs
and responsible for reproduction
iii. Gravid: filled with fertilized eggs

9. 5- Eggs: contain hexacanth
embryo (oncosphere).
6- All cestodes have an intermediate host except Hymenolepis nana.

10. Examples of Class Cestoda
1- Taenia sp.
Taenia saginata
Taenia solium
2- Hymenolepis sp.
Hymenolepis diminuta
Hymenolepis nana
3- Dipylidium caninum
4- Echinococcus granulosus

11. General life cycle of Cestodes
1. The adult worm matures in human intestine (final host).
2. Eggs shed in feces are released into environment.
3. Eggs are eaten by grazing animals (intermediate host).
4. Larval forms encyst in animals’ tissue.
Humans ingest encysted larvae in meat of infected animal (except in case of Echinococcus granulosus).

12. Taenia saginata (Beef Tape Worm)
Length: up to 10 m
Taenia saginata mature segment: nearly square, bilobed ovary, scattered testis, uterus: median tube
(magnifier)
Taenia saginata gravid segment longer than broad branched uterus filled with eggs
(magnifier)

13. Taenia sp.
Egg
circular, radiating (striated) double wall
(H.P)

14. Taenia saginata Location of adult: small intestine of man
Intermediate host : cattle (beef)
Infective stage : Cysticercus bovis
Mode of transmission: eating insufficiently cooked meat containing Cysticercus bovis
Diagnosis: eggs & gravid segments in stool
Disease: Taeniasis

15. Hymenolepis diminuta (Rat Tape Worm)
Length: cm
Mature segments: Broader than long characterized by 3 testis and one ovary in each segment (magnifier)
Gravid segments: Broader than long, enlarged uterus containing eggs (magnifier)

16. Hymenolepis diminuta
Location of adult: small intestine of rat occasionally man
Intermediate host: rat flea
Infective stage: cysticercoid
Mode of transmission: ingestion of rat flea containing cysticercoid
Diagnosis: eggs and gravid segments in stool
Disease: hymenolepiasis

17. Hymenolepis nana (Dwarf Tape Worm)
Length: Very small mm
Mature segments: broader than long, characterized by 3 testis and one ovary in each segment (L.P)

18. Hymenolepis nana Location of adult: small intestine of man
Intermediate host: none
Infective stage: eggs
Mode of transmission: eating food contaminated with eggs or autoinfection
Diagnosis: eggs in stool
Disease: Hymenolepiasis

19. Dipylidium caninum (Dog Tape Worm)
Length: cm
Cucumber seed-like or barrel shape
Mature segment: Longer than broad, 2 genital pores, testis and ovaries
(magnifier)
Gravid segment: Longer than broad, deformed wall, enlarged uterus filled with eggs
(magnifier)

20. Dipylidium caninum Egg Packet: round to oval and containing 5-15 eggs
(H.P)
Scolex: showing 4 suckers and extended rostellum with four rows of hooks (L.P)

21. Dipylidium caninum
Location of adult: small intestine of dogs, occasionally man
Intermediate host: dog flea
Infective stage: cysticercoid
Mode of transmission: ingestion of dog flea containing cysticercoid
Diagnosis: egg packet in stool
Disease: Dipylidium caninum infection

22. Echinococcus granulosus (Hydatid Tape Worm)
Length: 3-9 mm
Adult worm: scolex, immature, mature and gravid segments
(4X)

23. Echinococcus granulosus Protoscolex from hydatid cyst
(H.P)

24. Echinococcus granulosus
Location of adult: small intestine of dogs
Location of hydatid cyst : liver, lung, CNS and bone in man, cattle and sheep
Intermediate host: cattle, sheep (man is an end stage intermediate host)
Infective stage (for human): eggs in feces
Mode of transmission:
man is infected by ingestion of eggs in dog feces
Diagnosis: identification of hydatid cyst by X-ray
Disease: hydatid disease