Schistosoma mansoni

Physiology and Structure

Resides in small branches of the inferior mesenteric vein near the lower colon.

The eggs are oval in shape and posses a sharp lateral spine.

 

 

 

 

Schistosoma mansoni egg

https://www.flickr.com/photos/ajc1/2693048966/

 

 

 

https://www.flickr.com/photos/15218842@N08/2370498968/

 

 

 

Clinical Syndromes

  •  Worms in the lungs may produce cough and upon reaching the liver, hepatitis may appear.
  • Flukes take up residence in the vessels and begin laying eggs. Upon doing so, fever, malaise and abdominal pain and tenderness of the liver may be observed.
  • Severe neurologic problems may follow when eggs are deposited in the spinal cord and brain.

 

 

Life Cycle:

 

Schistomes_LifeCycle.gif

 

taken from:  https://www.stanford.edu/class/humbio103/ParaSites2004/Schisto/Schistomes_LifeCycle.gif

 

 Treatment, Prevention and Control

  • Antihelminthic therapy may terminate oviposition (egg laying) but it does not afftect lesions caused by eggs which are already deposited in tissue.
  • Improved sanitation and control of human fecel deposits are critical in ensuring that the infection does not spread.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

We do not take credit for any of the information found in this website. All the information is obtained from various forms of literature.

Parasite is defined as an organism that derives its nutrients from another living organism, the host. Parasitic diseases are usually referred to those caused by protozoa, helminths and arthropods which love at the expense of their host. Successful parasites are the ones who are able to maintain their own life processes without killing their host.

Several ways to distinguish parasites infection and bacteria/viruses infection:

  1. Parasites have a complex life cycle that involves the formation of resistant cyst in the organism. (it can usually survive for long periods outside the host.)
  2. Life cycle might involve an insect vector (carrier) that is important for the transmission of disease. In most cases, it is impossible to eliminate the vector effectively.
  3. Some parasites are capable of infecting both humans and animals, thus both can act as reservoirs for the infection. This is true for most protozal infections carried by insects.
  4. Many parasites has life cycle that requires enough time to allow for the various stages to mature, either in soil or in an insect or host.