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Difference between Taenia solium and Taenia saginata 

Taeniasis is the parasitic infection of humans caused by adult tapeworm species; i.e. Taenia saginata (beef tapeworm)Taenia solium  (pork tapewormor Taenia asiatica (Asian tapeworm). T. solium and T. saginata have a worldwide distribution but incidence is higher in developing countries where as  Taenia asiatica is limited to Asia.

T. solium tapeworm infections can lead to human cysticercosis.

The major differences between T. solium and T. saginata is 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 (sometime 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 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- 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 Taenia solium and Taenia saginata are  morphologically indistinguishable.
Eggs of Taenia solium and Taenia saginata are morphologically indistinguishable.
 Eggs (Infectious nature)  Infectious to humans (Human who ingested  food contaminated with egg of Taenia solium may develop cysticercosis)  Eggs of Taenia saginata are not infectious. Human who ingest T. saginata eggs do not develop cysticercosis.

 

Note: Most of the photo of the parasite posted here are taken from Website of CDC