Trichuris trichiura

parasiology lecture

1. Trichuris trichiura The whipworm Lecture by: Maha Gamal A ldein

2. Introduction Trichuris trichiura or Trichocephalus trichiuris is intestinal nematode worm Inhabit a human large intestine ( ceacum ) Causing the disease known as trichiuriasis I t is soil transmitted infection (eggs are infective stage found in soil) I s commonly known as the whipworm because it looks like the whip 2

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4. The worms has thin anterior and thick posterior part They attach to intestinal mucosa by embedding their anterior part. T hey feed on tissue fluid (not blood). 4

5. Geographical distribution: Worldwide distribution It is more common in Asia L ess in Africa and South America . R are in the United states. 5

6. Morphology (the worm) Shape : round narrow long anterior part end and shorter and thicker posterior. Color : pinkish-white Size: ♀ 35–50  mm long ♂ 30–45   mm, with a coiled posterior end 6

7. Eggs of Trichuris trichiura Shape : oval ( barrel-shaped) has polar hyaline mucoid blugs Size : 60 x40 µm Color : honey brown Shell : T hick Contents: Mass of granules ( Unembryonated ) 7

8. T. trichura eggs 8

9. Development of T. trichura eggs 9 1-Eggs are single celled when passed with human feces 2-The develop into 2 cell, 4 cell, morula , egg contain larva (in soil ) 3-Thelarvated egg (infective to human) The development of infective eggs in soil takes about 2-3weeks ,

10. How man become infected? Infection to man is by ingestion of the infective eggs (contain larva) that may be in contaminated food or drink, hands with soil The larva hatch in the human small intestine then migrate to large intestine They attach to mucosa of the large intestine. Then develop into mature worms with in three months After mating female produce 2,000–10,000 single-celled eggs per day which come out with feces. Worms can live up to five years 10

11. Life cycle 11

12. Pathology & Symptomatology People with light infections usually have no symptoms . People with heavy infection show symptoms like: Frequent defecation P ainful passage of stool S tool appearance: contains a mixture of mucus and blood (dysentery). The clinical feature is identical to amebic dysentery. 12

13. Complications: Colonic obstruction because of the tangle of worms U lceration of large intestine which result in blood loss. I ron deficiency anemia Rectal prolapse 13

14. Rectal prolapse 14

15. Laboratory Diagnosis 1- what is /are suitable sample/s? 2- what is are suitable diagnostic test/s or technique/s? 3- what is/are the diagnostic stage/s? 15

16. Summary : T. trichuria worm inhabit human large intestine T he female produces large number of eggs 2,000–10,000 per day The worms are not found stool because they attach to the mucosa of large intestine. 16

17. 1- Stool sample is suitable for the diagnosis. 2- suitable diagnostic technique: A- direct wet examination for feces (heavy infection) B-Concentration by sedimentation or by floatation to detect (very light infection) 3- diagnostic stages: eggs 17

18. Quality control Eggs of T. trichiura should be differentiated from Capillaria philippensis eggs which may also found in stool. C. Philippensis egg T.trichiura egg 18

19. Treatment Several anthelmintics drugs of choice: A lbindazole Mebendozle Prognosis The prognosis is good in light infection Poor in heavy chronic infection 19

20. Prevention & control Prevent contamination of soil with human feces Construction of latrines Washing hands before eating (children, soil worker). Washing vegetables & fruits Do not use the night soil as fertilizer 20