Blood

• Schistosoma spp.


  Scientific name
• Schistosoma japonicum


  Oriental blood fluke
• Schistosoma mansoni


  Manson's blood fluke

  
• Schistosoma haematobium


  Vesical blood fluke
• Schistosoma intercalatum


  African blood fluke
• Schistosoma mekongi


  Mekong river blood fluke
• Schistosoma intercalatum and Schistosoma mekongi are minor Schistosoma spp.
• S. mekongi is almost the same with the S. japonicum
• S. intercalatum is almost the same with the S. haematobium
• Habitat of Schistosoma japonicum, Schistosoma mekongi


  Superior mesenteric vein, draining the small intestine

  
• Habitat of Schistosoma mansoni, Schistosoma intercalatum

  Inferior mesenteric vein, draining the large intestine

  
• Habitat of Schistosoma haematobium


  Vesical and pelvic venous plexus, urinary bladder
• Definitive hosts


  • Humans
• Definitive and Reservoir Hosts for Schistosoma japonicum


  • Dogs
  • Pigs
  • Cats
  • Carabaos
  • Cows
  • Rodents
  • Monkeys
• Definitive and Reservoir Hosts for Schistosoma mansoni, Schistosoma haematobium

  • Monkey

  
• Intermediate hosts for Schistosoma japonicum

  • Oncomelania hupensis quadrasi

  
• Intermediate hosts for Schistosoma mansoni

  • Biomphalaria spp.

  
• Intermediate hosts for Schistosoma haematobium


  • Bulinus spp.

  
• Adult Worm: Ingest erythrocytes (RBC)


  Hemoglobinase: breaks down globulin and hemoglobin

  
• The broken down hemoglobin can become food and will be digested
• Adult worms utilize glucose at a rapid rate
• Adult worms are presumed to absorb nutrients through their body walls
• Adult Male Schistosoma japonicum


  • Elongate, cylindrical in shape
  • 12 - 20 mm by 0.5 - 0.55 mm
  • Oral and ventral suckers are close to each other
  • With gynecophoric canal
  • Non-tuberculate integument
  • Testes: 6 - 8, slightly lobate in single column
• Schistosoma mekongi resembles Schistosoma japonicum
• The tegument of Schistosoma japonicum and Schistosoma mekongi is non-tuberculated making it appear smooth without spines
• Adult Male Schistosoma mansoni

  • Elongate, cylindrical in shape
  • 6 - 14 mm by 1.1 mm
  • Oral and ventral suckers are close to each other
  • With gynecophoric canal
  • Grossly tuberculated integument
  • Testes: 8 - 9, in zig zag arrangement
• Adult Male Schistosoma haematobium

  • Elongate, cylindrical in shape
  • 19 - 15 mm by 0.8 - 1 mm
  • Oral and ventral suckers are close to each other
  • With gynecophoric canal
  • Finely tuberculated integument
  • Testes: groups of 4 - 5 testes behind the ventral sucker
• Schistosoma intercalatum resembles Schistosoma haematobium
• Adult Female Schistosoma japonicum

  • Slender, delicate, smooth
  • 26 mm by 0.3 mm
  • Ovary at middle of the body with genital pore behind the ventral suckers
  • Uterus with 50 - 100 eggs at a time
  • Location: Mesenteric veins

  
• The presentation of Schistosoma japonicum is chronic hepatic schistosomiasis

  
• Adult Female Schistosoma mansoni


  • Slender, delicate, smooth
  • 14 mm by 0.25 mm
  • Ovary at anterior half of the body
  • Uterus with 1 - 3 eggs at a time
  • Location: Mesenteric veins

  
• Adult Female Schistosoma haematobium


  • Slender, delicate, smooth
  • 20 mm by 0.25 mm
  • Ovary at posterior half of the body
  • Uterus with 20 - 30 eggs at a time
  • Location: pelvic veins

  
• Schistosoma spp.


  • S. haematobium: Finely tuberculated
  • S. mansoni: Grossly tuberculated
  • S. japonicum: Very smooth; no tuberculations
• Surface Turnover


  Schistosoma mansoni shed their teguments in abundance which can neutralize antibody response at a distance away from the parasite
• Antigen mimicry


  Schistosoma produces antigens similar to host antigens so they are not recognized by the host's immune system
• Antigen Disguise


  Adult Schistosoma cover themselves with host proteins to be considered as self and will not be attacked by the immune factors
• Unlike antigen mimicry where the parasite mimics the antigen, in antigen disguise the parasite assimilates host antigen into its tegument
• Schistosoma japonicum ova


  • Ovoidal to round
  • 700 - 1000 um by 50 - 65 um
  • Thin-shelled, rough beaded outer surface, pale yellow in color
  • Lateral, short, sometimes curved spinous knoblike process
  • Embryonated
  • Location: Veins of intestine and rectum
  • Exit: Feces

  
• Schistosoma mansoni ova


  • Elongate, oval
  • 155 um by 60 um
  • Yellowish brown, transparent shell
  • Lateral long spine
  • Embryonated
  • Location: veins of colon, rectum, mesenteric glands, occasionally bladder
  • Exit: feces, rarely urine

  
• Schistosoma haematobium ova


  • Elongate, oval/spindle: round anteriorly, conical posteriorly
  • 112 - 170 um by 50 um
  • Light yellowish-brown transparent shell
  • Terminal delicate spine
  • Partly mature when laid with miracidium
  • Location: veins of bladder, occasionally rectum, pelvis, lymph glands
  • Exit: Urine, rarely feces