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{{Taxobox
 
{{Taxobox
|name               =''Leishmania spp.''
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|name =''Leishmania spp.''              
|kingdom           =Eukaryota
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|kingdom =Eukaryota          
|sub-kingdom        =
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|sub-kingdom =        
|phylum             =Euglenozoa
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|phylum =Euglenozoa            
   −
|super-class        =
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|super-class =        
|class             =Kinetoplastea
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|class =Kinetoplastea            
|sub-class          =
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|sub-class =          
|super-order        =
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|super-order =        
|order             =Trypanosomatida
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|order =Trypanosomatida            
|sub-order          =
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|sub-order =          
|super-family      =
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|super-family =        
|family             =Trypanosomatidae
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|family =Trypanosomatidae            
|sub-family        =
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|sub-family =          
|genus             =Leishmania
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|genus =Leishmania            
|species           =''L. infantum'', ''L. donovani'', ''L.chagasi''
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|species =''L. infantum'', ''L. donovani'', ''L.chagasi''          
 
}}
 
}}
 
[[Image:Leishmania Life Cycle.jpg|thumb|right|150px|Leishmania Life Cycle - Wikimedia Commons]]
 
[[Image:Leishmania Life Cycle.jpg|thumb|right|150px|Leishmania Life Cycle - Wikimedia Commons]]
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''Leishmania spp.'' are ovoid shaped parasites containing a rod shaped 'kinetoplast'. The kinetoplast is associated with a rudimentary flagellum that does not extened beyond the cell margin. The position of the kinetoplast changes as the parasite changes between life stages. Once ingested by a [[Biting Flies#Psychodidae|sand fly]] the parasite takes the promastigote form and the kinetoplast moves the the posterior of the cell.
 
''Leishmania spp.'' are ovoid shaped parasites containing a rod shaped 'kinetoplast'. The kinetoplast is associated with a rudimentary flagellum that does not extened beyond the cell margin. The position of the kinetoplast changes as the parasite changes between life stages. Once ingested by a [[Biting Flies#Psychodidae|sand fly]] the parasite takes the promastigote form and the kinetoplast moves the the posterior of the cell.
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==Life Cycle==
 
==Life Cycle==
*Transmitted by blood sucking [[Psychodidae|sand flies]]
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The life cycle of ''Leishamania spp.'' requires transmission between mammalian (and occasionally reptile) hosts by a blood sucking fly. The [[Psychodidae|sand flies]] is the intermediate host, in the Old World the flies are of the genus ''Phlebotomus'' and in the New World they are of the genus ''Lutzomyia''.
**''Phlebotomus'' spp. in the Old World
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The amastigote form which lacks a flagella is found in he vertebrate hosts [[Macrophage|macrophages]]. The amistgote is ingested by the sand fly whilst it feeds on the host, once ingested the ''Leishamnia'' will transform into the flagellated promastigote form in the insect gut. Replication by binary fission occurs in the insects gut followed by migration to the proboscis of the insect. The presence of ''Leishamnia'' in the insects proboscis allows innoculation of the next host on which the fly feeds with the ''Leishmania'' parasite. Crushing the sand fly on the skin of a mammal can allow percutaneous transmission.
**''Lutzomyia'' spp. in the New World
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Once inside the vertebrate host the ''Leishmania'' will invade the hosts [[Macrophage|macrophages]] and having done this revert to the amastigote form.
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*The amastigote (morphological form) is found in vertebrate [[Macrophage|macrophages]]
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==Pathogenesis==
 
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Infection with ''Leishmania'' can produce either cutaneous or viscreal disease as the infected macrophages proliferate in foci. There is a very long incubation period from infection to pathology, which can take years and therefore many infected dogs either never become symptomatic or remain so for a long period of time.
*Ingested by [[Psychodidae|sand fly]] during feeding
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**Transforms in [[Insecta|insect]] gut
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  −
*Multiplies and migrates to [[Insecta|insect]] proboscis
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**Inoculated during feeding
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**Can be transmitted percutaneously if [[Psychodidae|sand fly]] crushed on skin
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  −
*Invades [[Macrophage|macrophages]] and reverts to amastigote
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*Multiplies by binary fission
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  −
'''Pathogenesis'''
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*Infection of vertebrate host
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**Produces foci of proliferating ''Leishmania''-infected [[Macrophage|macrophages]] in skin ('''cutaneous''') or internal organs ('''visceral''')
      
*Very long incubation period
 
*Very long incubation period
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*Many infected dogs are asymptomatic
 
*Many infected dogs are asymptomatic
   −
*Cutaneous form  
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*Cutaneous form
 
**Produces areas of ulceration on pinnae of [[Ear - Anatomy & Physiology|ears]], eyelids or on the [[Lips - Anatomy & Physiology|lips]]
 
**Produces areas of ulceration on pinnae of [[Ear - Anatomy & Physiology|ears]], eyelids or on the [[Lips - Anatomy & Physiology|lips]]
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'''Diagnosis'''
 
'''Diagnosis'''
*Demonstrate ''Leishmania'' organisms  
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*Demonstrate ''Leishmania'' organisms
 
**In skin scraping or smears
 
**In skin scraping or smears
 
**In joint fluid, [[Lymph Nodes - Anatomy & Physiology|lymph node]] or [[Bone Marrow - Anatomy & Physiology|bone marrow]] biopsies
 
**In joint fluid, [[Lymph Nodes - Anatomy & Physiology|lymph node]] or [[Bone Marrow - Anatomy & Physiology|bone marrow]] biopsies
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'''Treatment and Control'''
 
'''Treatment and Control'''
 
*Chemotherapy
 
*Chemotherapy
**Prolonged treatment, expensive, suppresses infection  
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**Prolonged treatment, expensive, suppresses infection
 
**Does not cure infection
 
**Does not cure infection
  
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