Trichinella spiralis

1. Tissue Nematodes Trichinella spiralis Raed Z. Ahmed, Medical Parasitology Lab.,2012

2. Life cycle Raed Z. Ahmed, Medical Parasitology Lab.,2012

3. Trichinella spiralis Cause trichinosis, trichiniasis or trichinelliasis.. Adult inhabit the small intestine of the rats, pigs and human. Both males and females lie freely in the lumen of the intestine of pigs, rats and human. Fertilized female only penetrate the mucosa where the larviposit, they do not lay eggs. Larvae is the infective stage, live encysted in the flesh of the host, and they represent the diagnostic stage. Human infected by eating undercooked pork containing infective encysted larvae. Human is dead end host. Raed Z. Ahmed, Medical Parasitology Lab.,2012

4. Continue……….. • Diagnosis: • Finding larvae in the blood during migration or in muscle after encystation. • Immunological tests. • X- ray to detect the calcified larvae in muscle. Raed Z. Ahmed, Medical Parasitology Lab.,2012

5. Trichinella spiralis larvae encysted in muscle Raed Z. Ahmed, Medical Parasitology Lab.,2012

6. Intestinal Nematodes Entrobius vermicularis Raed Z. Ahmed, Medical Parasitology Lab.,2012

7. Life cycle Raed Z. Ahmed, Medical Parasitology Lab.,2012

8. Entrobius vermicularis Also named as human pin worm and seat worm, cause oxyurdiasis. Young and mature worms are present in small intestine (at terminal ileum till fertilization). Gravid females are present at lower rectum where they lay ova at perianal region around anus (oviparous). The female is 0.88-1.3 cm long, it has a long tapering tail resembling 1/3 its length, its strait. The male is shorter than female (2-5 mm) the tail is curved strongly to ventral side, and has a single spicule. Infective stage: Embryonated Eggs. Definitive host: human. Raed Z. Ahmed, Medical Parasitology Lab.,2012

9. Continue……… • Diagnosis: • Egg in stool is rarely detected but adults present after purgative. • Egg can be detected at perianal area as follow: • N.I.H method (National Institute of Health), its based on swabbing the perianal area with a cellophane paper. • The adhesive cellulose tape (scotch tape), better result. • The Vaseline cloth wiping, the collected ova examined. • Egg morphology: • 20-50u, transparent with double walled shell, it may show one side convex and the other flat. Raed Z. Ahmed, Medical Parasitology Lab.,2012

10. Entrobius vermicularis Eggs Raed Z. Ahmed, Medical Parasitology Lab.,2012

11. Entrobius vermicularis Adult female male Raed Z. Ahmed, Medical Parasitology Lab.,2012

12. Intestinal Nematodes Trichuris trichiura Raed Z. Ahmed, Medical Parasitology Lab.,2012

13. Life cycle Raed Z. Ahmed, Medical Parasitology Lab.,2012

14. Trichuris trichiura • Its commonly called whip worm because of the shape of this worm (anterior thin and posterior thick). • Adult inhabit the large intestine in the caecum of man. • The adult male smaller than female, male 3.4-4.5 cm, female 4-5 cm. • Trichuris trichiura eggs have distinct shape. (oviparous) • Diagnosis: • Stool examination to detect eggs. Raed Z. Ahmed, Medical Parasitology Lab.,2012

15. Trichuris trichiura Eggs Raed Z. Ahmed, Medical Parasitology Lab.,2012

16. Trichuris trichiura Adult Raed Z. Ahmed, Medical Parasitology Lab.,2012