Introduction to parasitology

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Parasitology:
    Medical parasitology deals with the study of parasites which infect and produce diseases in human beings.


Protozoal

Helminths
   
 1. Amoeba
    Entameba histolytica    
    E.gangivalis                                    
    Balantidium

     1. Trematodes
    Faciola species
    Schistosoma species                

     2.Flagellates
    Giardia lamblia
    Tricomonas vaginalis
    Lieshmania species		     
2. Nematodes
    Round Worm
    Hook Worm
    Thread Worm

     3.Sporozoa
    Plasmodium vivax
    Plasmodium falciparum
    Toxoplasma gondi		    
 3. Cestode
    Taenia species
    Echinococcus species


   
  4.Ciliates
    Balantidium

 
Mode of Transmission:
  1. Contaminated soil and water
  2. Under cooked food
  3. Fish
  4. Crab and Cray fish
  5. Cyclops
  6. Water cress
  7. Blood sucking insects
Portal of Entry:
  1. Mouth
  2. Skin
  3. sexual contact
  4. Congenital
Types of Host:
  1. Definitive Host: Parasite undergoes sexual reproduction.
  2. Intermediate Host: Larva or Sexual stage of parasite.
  3. Paratenic Host:Parasite survive but does not develop.
  4. Reservivor Host: Harbours parasite and act as source of infection.
Types of Parasite:
  1. Ectoparasite
  2. Endoparasite
  3. Obligate parasite
  4. Facultative parasite
  5. Accidental parasite
  6. Aberrant parasite
Laboratory Diagnosis:
1. Specimen:
  • Stool
  • Blood
  • Urine
  • Genital specimen
  • CSF
  • Sputum
  • Tissue and Aspirates
2. Direct demonstration:
  • Saline mount
  • Iodine mount
3. Serological tests:
  • ELISA (Enzyme Linked Immuno Sorbant Assay)
  • IHA (Immuno Hemato Assay)
  • IFA (Indirect Fluorescence Assay )
4.Skin tests
5. Molecular methods
  • PCR (Polymerase Chain Reaction)





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