Taenia solium (Pig tapeworm) Life cycle Diagnosis

Pig tapeworm

Taenia solium:

Disease in human;

Taenia soliumCysticercosis / Porcine and Human Cysticercosis / Pork measles.

Morphological and Biological features:

• Scolex has rostellum armed 2 concentric rows of hooks(22 to 32 hooks).
• Large tapeworm (3-4m, sometimes 7m.)
• Metacestodes developed in the muscles of pig, dog and man.
• Metacestode are Cysticercus cellulosae.
• The cyst is white, ovoid, up to 1.8 cm. in diameter, is enclosed in a thin fibrous capsule.
• A mature T. soliummay consist of 800-1000 segments.
• Veterinary significance is little but public health i.e. zoonotic significance is high.
• 3 lobed ovary.

Life cycle:

Indirect life cycle, where;

I/H: Pig, wild boar (man).

F/H: Man.

Larval site (Cysticercus cellulosae) in I/H

• Usually in striated muscle and heart.
• Liver, lung, kidney, eye, lymph node.
• Subcutaneous tissue(s/c)
• CNS.

·         Infected  human (F/H)

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·         passing millions   of eggs daily or intact segments each with 250,000eggs in the human feces

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·         . eggs survive pasture for several months .

·         Ingestion by a pig (I/H) (from pasture /utensils)

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·         onchosphere travel via the circulation (blood  lymph )to the striated muscle .

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·         Two weeks later develop into pale semitransparent spot

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·         About 10 weeks later.

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·         It reaches to its full size ,length 1cm. ( scolex (A large pea)®6-9 mm length into 5 mm in size) i.e.cysticercus cellulosae .

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·         Ingestion of raw /inadequate cooked pork by man.

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·         Man become infected

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·         Adult developed in S I.(within 2 months)

·         Longevity of the cyst ®from several weeks to  years.

Clinical signs:

Pig: Usually no clinical signs.

Man: As an I/H; human cysticercosis / T. soliumcysticercosis. Rarely produces serious effects. Severity depends on location and number of cysticeri

1. Cyst developing in the brain and spinal cord or in the eye. Usually cause fetal effect.
2. Some clinical sign in man (Muslims are usually not effected due to their religious restriction of pork).
3. Rheumatic pains.
4. Mental disturbances.
5. Seizures.
6. Hydrocephalus
7. Epilepsy
8. Loss of vision
9. Death due to acute intracranial hypertention.
10. Pork muscle is appeared when man takes infected pork.

Diagnosis:

1. Clinical history
2. Slaughterhouse carcass inspection 
• Striated muscles.
• Heart, lung
• Liver, kidney, lymph nodes.
• Eye
• Subcutaneous tissue
• CNS (brain and spinal cord)

 (Rules are unfit for consumption if two or more living cyst are found at more than one inspected site)

Treatment:

The cyst can be killed in pig by elevated doses of Paraziquintel (50mg/kg b.w.).

Control:

v  Exclusion of pig from contact with human feces.

v  Treating infected person and providing health education and adequate sanitary facilities.

v  General practices of cooking meat thoroughly.

v  Compulsory meat inspection.

v  Heavy infected carcass should be condemned