Taeniasis is the parasitic infection of humans caused by adult tapeworm species; i.e. Taenia saginata (beef tapeworm), Taenia solium (pork tapeworm), or Taenia asiatica (Asian tapeworm). T. solium and T. saginata have a worldwide distribution but the incidence is higher in developing countries whereas Taenia asiatica is limited to Asia.
T. solium tapeworm infections can lead to human cysticercosis.
The major differences between T. solium and T. saginata are summarized in this table:
Properties
Taenia solium
Taenia saginata
Common Name
Definitive host
Human
Human
Intermediate Host
Pig
Cow/Cattle
Disease
Taeniasis and Cysticercosis
Taeniasis only
Transmission
Infection is common among those eating raw or insufficiently cooked measly pork containing the cysticerci.
Human beings are infected through the eating of undercooked beef containing the cysticerci (“measly” beef)
Size
Size of adult worm: 2-7 m
Size of adult worm: 5 m or less (sometimes up to 25 m)
Scolex
The scolex head is globular in outline and has four circular suckers.
The head is provided with the rostellum armed with a double row of alternating large and small hooklets. The rostellar hooklets are shaped like daggers or Arbian poniards (armed scolex)
The scolex (“head”) is quadrate in outline and has four circular suckers.
Rostellum and hooklets are absent (i.e. unarmed scolex)
Proglottids
The total number of proglottids (segments) is an average of 1000.
The gravid uterus consists of a median longitudinal stem with 5- 13 compound lateral branches on each side
The gravid segments are expelled passively, in chains of 5-6 at a time, and not singly.
T. solium may produce 50,000 eggs per proglottid.
The number of proglottids varies from 1000 to 2000.
The gravid uterus consists of a central longitudinal stem with 15-30 lateral branches on each side; these in turn sub-branch leaving practically no space in between.
The gravid segments are expelled singly
T. saginata may produce up to 100,000 eggs per proglottid.
Eggs
The eggs are about 30-35 micrometers in diameter and are bile stained.
The internal oncosphere contains six refractile hooks.
The eggs are not floated in the saturated solution of NaCl.
Eggs of Taeniasolium and Taeniasaginata are morphologically indistinguishable.
Eggs of Taeniasolium and Taeniasaginata are morphologically indistinguishable.
Eggs (Infectious nature)
Infectious to humans (humans who ingest food contaminated with eggs of Taenia solium may develop cysticercosis)
Eggs of Taenia saginata are not infectious. Humans who ingest T. saginata eggs do not develop cysticercosis.
Note: Most of the photos of the parasite posted here are taken from Website of CDC
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I am Tankeshwar Acharya. Blogging is my passion. As an asst. professor, I am teaching microbiology and immunology to medical and nursing students at PAHS, Nepal. I have been working as a microbiologist at Patan hospital for more than 10 years.
5 thoughts on “Taenia solium vs. Taenia saginata ”
Very nice post. I was looking for the lateral branches and found your table very useful. Consider adding treatment for completeness!
Sir i greatly admire you for your work. Please help us with specialized lab diagnostic procedures with each topic. Thank you for this worderful website! 😁
You clearly indicated the difference between T.saginata and T. solium. I think both adult stages of this helminths can be found in man producing eggs but the cystic stage of T. Saginata is not infective to man but the cystic stage of T. Solium is infective and cause cysticercosis in man accidentally or due to reverse peristalysis. You see reverse peristalsis also occurring in case of T saginata. But what do you think that eggs of teania saginata does not infect human but that of T solium is infective? Why? I need some infornation.
Taenia saginata dont have hooklets found in the scolex but some sources say the oncosphere has 6 hooklets. Is this true? if so, how does it go from a hexacanth embryo just like T.solium to a scolex without hooklets
Taenia solium, also known as pork tapeworm, causes Taeniasis, an infection that is common amongst people eating raw or insufficiently cooked measly pork containing the cysticerci. Taenia solium is...
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Very nice post. I was looking for the lateral branches and found your table very useful. Consider adding treatment for completeness!
Sir i greatly admire you for your work. Please help us with specialized lab diagnostic procedures with each topic. Thank you for this worderful website! 😁
You clearly indicated the difference between T.saginata and T. solium. I think both adult stages of this helminths can be found in man producing eggs but the cystic stage of T. Saginata is not infective to man but the cystic stage of T. Solium is infective and cause cysticercosis in man accidentally or due to reverse peristalysis. You see reverse peristalsis also occurring in case of T saginata. But what do you think that eggs of teania saginata does not infect human but that of T solium is infective? Why? I need some infornation.
I appreciative this scientific facts
Taenia saginata dont have hooklets found in the scolex but some sources say the oncosphere has 6 hooklets. Is this true? if so, how does it go from a hexacanth embryo just like T.solium to a scolex without hooklets