Diff Distribution Morphology Adult Male Size Post end Spicules Female Size Caudal end Vulva Oe Eggs Shape
Ascaris lumbricoides
Cosmopolitan
Entrobius vermicularis
Cosmopolitan (widest dist)
Ancylostoma duodenale
Tropical and sub tropical
Necator americanus
Tropical and sub tropical
Strongyloides stercolaris
Tropical and sub tropical
Trichostrongylus colibriformis
Cosmopolitan (esp. agri countries)
Capillaria philippenensis
Trichuris trichiura
Cosmopolitan
Trichnella spiralis
Cosmopolitan where pork is eaten.
2 alae. 20 cm Curved 2 separate 5 mm Curved 1
slight bend. 1 cm x 0.5 mm Copulatory bursa (1) 2 separate
More bent . 0.8cm 2 fused 0.7 mm x 60 μ Curved (gubernaculum) 2 separate
Attenuated ant end. 4-5 mm Copulatory bursa 2 separate 3 mm 3cm Curved 1 in retractile sheath 6 mm 4-5 cm St & blunt 3/4 1/4 Club-shaped Hen’s egg Ovoid 3/5 2/5 Narrow cellular 200 000 Barrel-shaped with 2 polar thickenings 50-20μ Brownish Immature (1 cell st) 1.5 mm Curved 2 lobular caudal appendages 3.5 mm Blunt (larviparous) 1/5 4/5 Cellular Larviparous
25 cm St 1/3 2/3 Club-shaped (m) Oval
10 mm Long pointed 1/4 3/4 Double bulbed D-shape e′ double layered shell & 3rd outer albuminous layer. 50-20 μ Colorless Full-developed larva.
1.2 cm x 0.6 mm With spine 2/3 /1/3 Club-shaped (mouth)(2) Oval with blunt poles
1 cm Without spine ½
2.2mm x 40μ \ 1 mm x 50 μ St 2/3 1/3 \1/2 Cylindrical Rh form Oval with thin shell
5-7 mm
Size Col Content Larva Life cycle Habitat Def. host Diag st Moults
60-40 μ Yellow brown Imm ovum
60-40 μ Colorless Immature (4 cell stage)
50-20 μ Translucent Mature Rh form larva Bifid tail
80-40 μ Translucent Immature (32 cell st) Knob Upper part of small int.
40 – 20 μ Yellow brown Un embryonated
Rh form
Small int
Filariform
Caecum and adjacent part of sm and large int. Man The gravid ♀ migrate 2 peri2 Larva (2) adult Small int (attached by the mouth to the mucosa) Man Eggs in faeces 4 Eggs (1-2) 1st st (5) 2nd st (7) filariform (ensheathed) Filariform (during mig.) 3rd moult (temporary buccal capsule) mature female (egg laying) Filariform larva Penetration of the skin by the larva (+ve thermo, histo & hydro/ -ve geo TROPISM)
Man Imm eggs in stools (average 200,000/day) 4 UFC 1st 2nd 2 in the lungs
Small int (& large int, proximal biliary & panc passages). Man (eggs r laid in the int mucosa & hatch into Rh larva(3) in faeces. 4 Rh 2 filari Larva (migrate) 2 adolescent. Filariform larva Penetration. (ext and int) Autoinfection
Small int.
Man and herbivores Imm eggs in stools.
Human (fish eating birds) Eggs in stool
Large int (thin portion in the submucosa) Man and some mammals Eggs in faeces
Adult sm int. Larva active ms. Man Encysted mature larva 4 in int
4 2 soil 2 in the host int.
No
No
Inf st Mode of infection
Eggs cont 2nd st. larva Ingestion
Anal region where the eggs r laid. Ingestion. Inhalation. Ext auto inf. Retro inf.
Filariform larva Ingestion of infected grass or raw vegetables Eating infected under cooked fish. Internal auto infection.
Embryonated eggs Ingestion of polluted water and raw vegetables
Encysted mature larva Ingestion of undercooked pork cont. inf st.
Migration
Life span
Eggs hatch in small int Rh larva int wall Vn lungs (2nd, 3rd moults) branch inf. (4th moult) Adults. 12-18 ms
No
Circulation rt side lung alveoli bronchi trachea pharynx (swallowed) (1W)
Circulation rt side lung alveoli bronchi trachea pharynx (swallowed) 5Ys (dir, indir, auto)(4)
No (on reaching sm int. it moults twice)
No
No
No
6-8Ys
4Ys
4-6Ys