Taenia saginata

Causes intestinal taeniasis

Morphology

Adult worm

• Comprises of head (scolex), neck and body.
• Body is divided into proglottids
• It has 4 muscular suckers on the scolex

Eggs

• Contain the embryo
• Embryo has 3 pairs of hooklets
• Eggs are bile stained

Larva

• Cysticercus is the larval stage
• Cysticercus bovis- larval stage of T. saginata

Life cycle

Definitive host: Man

Intermediate host: cattle

Infective form: larva (cysticercus)

Transmission- man eats undercooked beef containing the larva

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Larvae develop into adults in human intestine

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Adult worms undergo self-fertilization

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Produce eggs

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Eggs are released into feces

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Eggs are ingested by cattle

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Eggs penetrate intestinal wall and reach skeletal muscles

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Transform into larvae and deposited as cysts

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The cycle is repeated

Clinical manifestations

• Mild abdominal pain
• Nausea
• Loss of appetite
• Perianal pruritus

Laboratory diagnosis

Stool examination

• Wet mount examination of stool to demonstrate eggs
• Specimen: Anal swabs can be used to collect fecal matter
• Bile stained eggs are detected
• Scolex is found rarely in stools

Antigen detection in stool

• Taenia specific antigen detection by ELISA– using polyclonal Taenia antibodies
  • cannot distuinguish between taenia species

Molecular methods

• PCR (targets mitochondrial DNA)
  • PCR can distuinguish between taenia species