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
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