Habitat:

1. Fasciola : bile duct of sheep, cattle, goat and buffalo.

2. Schistosoma mansoni: radicals of inferior mesenteric vein draining large intestine and ileum
3. Heterophyes heterophyes : small intestine of man, cat, dog and fish eating birds
4. Diphyllobothrium latum: small intestine of man and fish eating mammals.
5. Taenia saginata : small intestine of man (proximal jejunum).
6. Taenia solium: small intestine of man.
7. Hymenolepis nana: small intestine of man mainly children.
8. Trichuris trichura: large intestine (caecum and rarely appendix).
9. Entrobius vermicularis: large intestine (caecum and appendix) mainly of children and female>male.
10. Capillaria philippinensis: small intestine in jejunum and birds act as reservoir host.
11. Ascaris : small intestine of man
12. Ancylostoma duodenal : small intestine of man , mainly in jejunum and proximal ileum but rarely in duodenum
except in heavy infection.
13. Strongyloids stercolaris: free living in soil or parasite in small intestine mainly duodenum and upper jejunum.
14. Entamoeba histolytica: lumen of large intestine
15. Giardia limblia: duodenum, upper jejunum , bile ducts and gall bladder
16. Balantidium coli: caecum and colon of man, pig, guina pig and rat
17. Isospora belli: duodenum and proximal jejunum of man only
18. Cryptosporadia: beneath the brush border of gastric and small intestine mucosa of man, calves, kittens,
puppies and rodents

Parasite that can cause dysentery:

1. Trichuris trichura
2. Schistosoma mansoni
3. Entamoeba histolytica
4. Balantidium coli

Parasites that can cause appendicitis:

1. Taenia saginata and solium (by their active gravid segment cable of creeping independent of the parent)
2. Trichuris trichura
3. Entamoeba histolytica (amoebic appendicitis)

Egg:

All are mature except:

Ascaris, Ancylostoma, Fasciola, Trichuris , Diphyllobothrium latum and Capillaria.

Only Strongyloids that have partially embryonated egg.

 1. Fasciola: operculated and large.
2. S.Mansoni: lateral spine and contain fully developed miracedium.
3. Heterophyes heterophyes: very small, operculated has knob like thickening on opposite sides of the shell and
contain fully developed miracedium.
4. Diphyllobothrium latum: immature, operculated when it become mature the embryo is ciliated hexacanth
embryo.
5. Taenia: 2 egg shell, the inner is thick brown striated embyrophore, the outer is thin hyaline capsule
surrounding hexacanth embryo or oncosphere.
6. H.Nana: 2 egg shell inner one containing 2 knob at opposite sides from which 4-8 filaments run in space
between outer and inner shell, it contain hexacanth embryo.
7. Trichuris trichura: barrel shaped, polar plugs and immature.
8. Entrobius vermicularis: larvated (mature), asymmetric flattened at one side and convex at the other
9. Capillaria: thick shell egg, unembyronated, flattened bipolar plugs and striated outer shell.
10. Ascaris: unfertilized egg: more elongated its present when female> male – fertilized egg: contain 3 shells inner
most us non permeable vitelline, middle is thick transparent and outer is mammillated albuminous layer (bile
stained) or may be absent (decorticated).
11. Ancylostoma: immature, thin shell, 4 cell stage, in constipated or well ventilated faeces may be morula or
larval stage.
12. Strongyloids: thin shell partially embryonated.

Intermediate host:

1. Fasciola : Lymnea trunculata.

2. Schistosoma: Biomphalaria
3. Heterophyes: 1st is Pirenella conica – 2nd bolty and boury
4. Taenia saginata: beef
5. Taenia solium: pig and man in case of cysticercosis.
6. Diphyllobothrium : 1st copepod crustacean eg. Cyclops or diaptomus – 2nd fish eg. Salmon, perch or trout.
7. Hymenolepis nana: man
8. Capillaria: fresh water or brackish water fish.

Mode of infection:

1. Fasciola: eating or drinking contaminated food (water vegetations eg. Lettuce) or drinks containing encysted
metacercaira.
2. S.Mansoni: penetration of unbroken skin by swimming in infective water or mucus membrane if he drinks
water infective by cercaria.
3. Heterophyes heterophyes: eating imperfectly cooked fish containing encysted metacercariae.
4. Diphyllobothrium: eating imperfectly cooked fish containing Plerocercoid larva
5. Taenia saginata: eating imperfectly cooked beef meat infected by Cysticercous bovis.
6. Taenia solium: eating imperfectly cooked pork meat infected by Cysticercous cellulosae.
7. Hymenolepis nana: autoinfection by ingesting the egg.
8. Trichuris: contamination of hand or food by larvated egg.
 9. Entrobius vermicularis: external and internal autoinfection and inhalation
10. Capillaria: autoinfection by larva or thin shelled egg, hyperinfection or ingesting imperfectly cooked fish
containing larva.
11. Ascaris: ingesting fully mature egg containing 2nd rhabditiform larva by contaminated food, hand or water or by
house flies.
12. Ancylostoma: penetration of skin in soil.
13. Strongyloids: penetration of skin in soil.
14. Entamoeba histolytica: ingestion of cyst form in contaminated food or drinks
15. Giardia : ingestion of cyst form in contaminated food or water- autoinfection- man to man and mechanical by
house flies
16. Balantidium coli: : ingestion of cyst form in contaminated food or drinks
17. Isospora belli: ingestion of mature sporulated oocyst form in contaminated food or drinks
18. Cryptosporadia: ingestion of mature oocyst through: contaminated food and drinks- close contact with calves-
autoinfection- direct person to person and inhalation

Autoinfection:

1. H.nana
2. Entrobius vermicularis
3. Capillaria
4. Giardia
5. cryptosporadia

Infective stage:
1. Fasciola : encysted metacercaria
2. Schistosoma : cercaria
3. Heterophyes : encysted metacercaria
4. Diphyllobothrium latum: Plerocercoid larva (wrinkled cuticle and non segmented)
5. Taenia saginata: cysticercous bovis
6. Taenia solium: cysticercous cellulosae
7. H.nana: egg
8. Trichuris: larvated egg
9. Entrobius: larva or thin shell egg
10. Ascaris: 2nd stage rhabditiform larva
11. Ancylostoma: 3rd stage filiariform larva
12. Strongyloids: 3rd stage filiariform larva
13. Entamoeba histolytica: mature 4 nucleated cyst
14. Giardia : cyst
15. Balantidium coli: cyst
16. Cryptosporadia: mature oocyst
17. Isospora belli: mature sporulated oocyst

Diagnostic stage:

1. Fasciola: egg
 2. Schistosoma mansoni: egg
3. Heterophyes: egg
4. Diphyllobothrium latum: egg or sometimes gravid segments
5. Taenia: gravid segment
6. H.nana: egg
7. Trichuris: egg
8. Entrobius: egg
9. Capillaria: egg, adult or larva in stool or adult in duodenal aspiration
10. Ascaris: egg in stool, larva in bronchial and gastric washing
11. Ancylostoma : egg (4 cell stage)
12. Strongyloids: rhabditiform larva or rarely egg in purgation of diarrhea or larva in sputum especially if the adult
in the lung
13. Entamoeba histolytica: in dysenteric stool  trophozoit, well formed stool cyst
14. Giardia : diarrhoeic stool  trophozoit, well formed stool cyst
15. Balantidium coli: trophozoit with or without cystic stage
16. Cryptosporadia: oocyst
17. Isospora belli: oocyst

Specimen:

1. Fasciola: stool and duodenal aspiration

2. Schistosoma: rectal swab- rectal biopsy- stool- sigmoidoscopcy and biopsy
3. Heterophyes, diphylloborthrium, taenia, H.nana, trichuris, Ancylostoma : stool
4. Entrobius: find egg under nails, perineal scraping or anal swab (early in the morning before washing)
5. Capillaria: stool or duodenal aspiration
6. Ascaris: bronchial or gastric wash or stool
7. Strongyloids : stool or sputum
8. Entamoeba histolytica: stool – sigmoidoscopcy , liver: X-ray and ultrasonography
9. Giardia : stool- duodenal aspiration and entero test
10. Balantidium coli: stool
11. Isospora belli: stool
12. Cryptosporadia: stool- entero test- intestinal biopsy and sputum examination

Concentration techniques:

1. Schistosoma: formol ether or kato technique

2. Ascaris: saline sedimentation, formol ether and MIFC
3. Ancylostoma , Strongyloids, giadria and isospora: zinc flotation technique
4. Cryptosporadia: formol ether and sheather's sugar flotation technique

Entero test:

1. Fasciola
 2. Strongyloids
3. Giardia limblia
4. Cryptosporadia

Separate sexes:

1. Schistosoma mansoni : male  6-9 testes , female  elongated ovary and the intestinal caeca unit
prequatorial
2. Trichuris: male  coiled posterior end, 1 long copulatory spicule , female straight caudal end
3. Entrobius : male  die after fertilization, female long pointed tai, double set of genetalia, prequatorial
valve, ,mouth opening posses 3 lips and esophagus is double bulbed
4. Capillaria : male  single spicule and the tail contain 2 papillae, female  value in esophageal region and
subterminal anus
5. Ascaris: mouth 3 lip, cylindrical esophagus , male  coiled posterior end, female  straight posterior end.
6. Ancylostoma: male  copulatory bursa and 2 spicules , female  straight posterior end.
7. Strongyloids: male curved tail and 2 spicules, female vulva at posterior 1/3

Male organs:

1. Fasciola and D.latum  cirrus and cirrus sac

2. Trichuris, E.vermicularis and capillaria  single copulatory spicule
3. Ascaris and Strongyloids  2 minuit spicules without copulatory bursa
4. Ancylostoma 2 minuit spicules with copulatory bursa

Esophagus:

1. Trichuris : schistome
2. E.vermicularis: double bulbed
3. Ascaris: cylindrical and larva is rhabtiform
4. Ancylostoma: club shaped and 1st, 2nd and 3rd stage larvae are filiariform while 4th stage is rhabditiform
5. Strongyloids: filiariform

Soil transmitted disease:

Environment  warm, high humidity, heavy rainfall, moisture retaining soil and dense shade

1. Trichuris
2. Ascaris
3. Ancylostoma
4. Strongyoids
Causes of malabsorption (MA) and malnutrition (MN) :

1. Capillaria (MA)
2. Diphyllobothrium (MN contribute the host for B12)
3. Ascaris (MN contribute the host for vit A and C)
4. Ancylostoma (MA  anemia and hypoprotenemia)
5. Strongyloids ( MA  steatorrhea)
6. Giardia (MA  steatorrhea, B12 and D-xylose)
7. Isospora (MA)

Pneumonitis:

1. S.mansoni( bilharizial cor pulmonle)

2. Ascaris (loeffler's syndrome)
3. Strongyloids
4. Ancylostoma (pribronchial or pneumonitis)

Cutanous lesions:

1. Fasciola (ectopic fasciolasis)

2. S.mansoni (pruritis)
3. Ancylostoma (ground itch)
4. Strongyloids( erythema- intense itching and peticeal hemorrhage)
5. Entrobius (nocturnal itching in anal region)
6. E.histolytica( due to rupture of liver abscess)