1. Class Cestoidea
Hymenolepis nana

2. Class Cestoidea, classification
A- Intestinal cestode :live in the lumen of intestine:eg
Taenia saginata
Taenia solium
Hymenolepis nana
B- Tissue cestodes: present within the tissue
(liver,lung,bone....)
Cysticercosis
Hydatid disease

3. Hymenolepis nana Disease :hymenolepiasis nana Morphology:1-3 cm,
scolex with 4 suckers and hooks,
neck,
immature segments,
mature segments,
gravid segments

4. Hymenolepis nana adults

5. Morphology Egg:spheroid, translucent, Internal 4-8 polar filaments
Cystocercoid:bladder like structure with the head in upright position

6. Cysticercoid (larval stage)

7. Life cycle 1- adult in the small intestine (definitive host)
2-Mature eggs pass with feces ( diagnostic AND infective stage)
3- NO( intermediate host)
4- The definitive host is infected by ingestion of food,drink contaminated with eggs ( mode of infection)

8. Very important auto infection
Types :
internal,eggs hatch in intestine,converted into cysticercoid,adult worms
External: feco-oral:lack of personal hygiene,person transmittes eggs from anus to mouth by contaminated hands,reach to stomach, hatch, converted into cysticercoid,in the intestinal wall, adult.

9. Signs and symptoms 1- in light infections,no symptoms
2- enteritis,colic,diarrhoea
3- dizziness and convulsion in children( neurotoxic effect)

10. diagnosis
1- clinical picture
2- finding eggs in stool

11. H.nana egg

12. Treatment
Niclosamide ( 2 gm) chewed and swallowed with a little amount of water

13. Prevention and control
1- personal cleanliness
2-treatment of infected persons
3- avoid contaminated food or drink