Taenia solium, the pork tapeworm, is a parasitic flatworm that can cause both taeniasis and cysticercosis in humans. It has a worldwide distribution except where pork is not consumed. The adult worm lives in the small intestine and eggs passed in stool can infect pigs, causing the larval stage cysticercus cellulosae. Humans can also become infected by ingesting eggs, with the larvae then developing in tissues throughout the body, commonly in muscles and the brain. Symptoms vary depending on the infected tissue but can include seizures, hydrocephalus, and neurological or psychiatric disturbances in neurocysticercosis. Diagnosis involves finding eggs, proglottids or antigens in

1. TAENIA SOLIUM
Shifa
58th batch
CMC

2. WHERE DOES IT BELONG?
order
order
Phylum
Class
Order
Family
Genus
species
Platyhelminthes( flatworms)
Cestoidea
Cyclophyllidea
Taenidae
Taenia
solium

3. Taenia solium - pork tape worm
Taenia - band/tape
Worldwide in distribution except in regions
and communities who don’t consume pork

5. Human small intestine, commonly in jejunum

7. Parts of adult T.solium
rostellum
proglottids

8. ADULT WORM
 2-3 m long
 Scolex small & globular(1mm)
 4 large cup like suckers(acetabula)
 Rostellum with double row of alternating round &
small dagger shaped hooks. (20-50 )
 Neck is short and half as thick
 Proglottids less than 1000

9.  Gravid segments are twice as long & broad.
 Testes composed of 150-200 follicles
 An accessory lobe for ovary
 Vaginal sphincter absent
 Uterus has 5 to 10 thick lateral branches
 A lateral thick lipped genital pore is present
alternating the right & left sides of adjacent
segments.
 Gravid segments pass passively out as short
chains. Eggs escape from ruptured uterus

10. EGGS
 Egg similar to T.saginata
 Spherical 30-40 micro.m
 Thin hyaline membrane around it which disappears
after release
 Inner embryophore radially striated & is yellow
brown due to bile staining.
 In the centre a fully developed embryo(oncosphere)
with 3 pairs of hooklets(hexacanth embryo)
 Eggs do not float in saturated salt solution
 Eggs are infective both pigs & humans.

11. LARVA
 Larval stage of taenia – cysticercus
 Of T.solium called cysticercus cellulosae


12. CYSTICERCUS
CELLULOSAE(BLADDERWORM)
 Infective form
 Develop in various organs of pig & human
 Ovoid,opalescent milky-white
 Measuring 8-10 mm in breadth and 5 mm in
length.
 Scolex of larva with its suckers lie
invaginated within the bladder
 It remains viable for several months.

14. When T.solium causes
taeniasis
 Definitive host - man
 Intermediate host – pig
 Infective stage - larva

15. When it causes cysticercosis
o Definitive host - man
o Intermediate - man
o Infective stage- eggs
o Mode of infection- by ingesting eggs
with contaminated food & water
o man harboring adult worm can auto
infect himself by unhygeinic habits or
reverse peristalsis.

16. o Oncospheres released in duodenum or
jejunum & penetrate intestinal wall
o They enter mesenteric venules & lymphatics
o Carried to different parts of body by
systemic circulation
o Filtered in to muscles & develop in to larval
stage in 60-70 days
o Larvae die without further development

19. Intestinal taeniasis
 caused by T.solium & T.saginata
 Sometimes asymptomatic
 When symptomatic causes abdominal
discomfort,indigestion,nausea,diarrhea&
weight loss
 Occasionaly acute appendicitis &
pancreatitis

20. Cysticercosis
• Caused by larval stage
• Larva-solitary or multiple
• Most common-subcutaneous tissue&
muscle
• Also affect-
eyes,brain,heart,liver,lungs,abdominal
cavity& spinlcord

21. • Larvae can evoke a cellular reaction starting
with infiltration of
neutrophils,eosinophils,lymphocytes,plasma
cells & giant cells
• Subcutaneous – asymptomatic
• Cysticercus surrounded by a fibrous capsule
except in eye & ventricles of brain

22. CLINICAL FEATURES-
Subcutaneous
cysticercosis
myocysticercosis
neurocysticercosis
oculocysticercosis

23. SUBCUTANEOUS CYSTICERCOSIS
 Mostly asymptomatic
 Subcutneous nodules

24. MYOCYSTICERCOSIS
 May cause acute myositis

25. NEUROCYSTIERCOSIS
• Most common & serious
• Adult onset epilepsy
• Hydrocephalous
• Psychiatric disturbances
• Meningoencephalitis
• Transient paresis
• Behavioral disorders
• Aphasia
• Visual disturbances
• Cause intracranial space occupying lesion

26. •
•
MRI of brain showing
neurocysticercosis

27. OCULAR CYSTICERCOSIS
Cysts found in vitreous humor,subretinal space & Conjunctiva
May present as blurred vision or loss of vision
Iritis ,uveitis & palpebral conjuctivitis

29. TAENIASIS
1. Stool examination
Eggs
 microscopic examination shows eggs
 Formol ether sedimention of method of stool
concentration useful
 Detected by cellophane swab method
 Species identification not possible

30. Proglottids
 Species identification possible using hand lens
 When gravid proglottid pressed between two
slides branching can be made out
 Only 13 lateral branches in T.solium

31. Detection of taenia antigen in feces
 ELISA using polyclonal antisera to
detect coproantigen
More sensitive than microscopy
Cannot differentiate between T.solium
T.saginata

32. Serodiagnosis
 specific abs detected by
 ELISA
 indirect immunoflouroscent test
 indirect hemgglutination (IHA) test
Molecular diagnosis
DNA probes & PCR to detect & differentiate b/n T.solium &
T.saginata

33. Others
Ocular cysticercosis-by opthalmoscopy
Eosinophilia in early stage

35. Intestinal taeniasis
 Single dose of praziquantel(10-20 mg)
 Nicolsamide (2 g) single dose
 Purgation is not necessary

36. Cysticercosis
 Excision best method
 Asymptomatic neurocysticercosis no treatment
 Symptomatic cerebral cysticercosis-praziquantel – 50
mg/kg in divided dose for 20-30 days
 Albentazole – 400 mg twice daily for 30 days
 Corticosteroids to reduce inflammatory reactions
 Antiepileptic drugs
 Operative intervention indicated for hydrocephalous

38.  Inspection for cysticerci in slaughter house
 Avoid undercooked pork
(temp 56 `c for 5 mts)
 maintain clean personal habits & general
Sanitary measures
 Prevention of fecal contamination
 Detection & treatment of hosts