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==''Leishmania''==
 +
[[Image:Leishmania Life Cycle.jpg|thumb|right|150px|Leishmania Life Cycle - Wikimedia Commons]]
 +
[[Image:Leishmania donovani.jpg|thumb|right|150px|''Leishmania donovani'' in bone marrow cell - Dr. L.L. Moore, Jr.]]
 +
[[Image:Leishmania tropica.jpg|right|thumb|150px|''L. tropica'' - Yutaka Tsutsumi, M.D., Professor, Department of Pathology, Fujita Health University School of Medicine]]
 +
*''Leishmania'' spp. are intracellular parasites of [[Macrophage|macrophages]]
 +
 +
*Are closely related to ''Trypanosoma'' spp.
 +
 +
*Cause diseases in humans, dogs and wild animals
 +
 +
*Present in southern Europe, Africa, Asia and South America
 +
 +
'''Life Cycle'''
 +
*Transmitted by blood sucking [[Biting Flies#Psychodidae|sand flies]]
 +
**''Phlebotomus'' spp. in the Old World
 +
**''Lutzomyia'' spp. in the New World
 +
 +
*The amastigote (morphological form) in found in vertebrate [[Macrophage|macrophages]]
 +
 +
*Ingested by [[Biting Flies#Psychodidae|sand fly]] during feeding
 +
**Transforms in [[Insecta|insect]] gut
 +
 +
*Multiplies and migrates to [[Insecta|insect]] proboscis
 +
**Innoculated during feeding
 +
**Can be transmitted percutaneously if [[Biting Flies#Psychodidae|sand fly]] crushed on skin
 +
 +
*Invades [[Macrophage|macrophages]] and reverts to amastigote
 +
 +
'''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 periods
 +
**Months to years
 +
 +
*Many infected dogs are asymptomatic
 +
 +
*Cutaneous form
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**Produces areas of ulceration on pinnae of ears
 +
 +
*Visceral form causes chronic wasting condition
 +
**Generalised eczema
 +
***Loss of hair around eyes producing 'spectacle' effect
 +
**Intermittent fever
 +
**Generalised lymphadenopathy
 +
 +
*Involved in [[Parasitic skin infections - Pathology#Protozoa|skin infections]]
 +
 +
'''Epidemiology'''
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*Disease dependent on [[Biting Flies#Psychodidae|sand fly]] vectors
 +
**E.g. Common in dogs around the Mediterranean coast, foci around southern Europe and around Madrid
 +
 +
*Reservoirs of infection
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**E.g. Wild animals such as rodents and stray dogs
 +
 +
*Mechanisms of transmission
 +
**Direct contact
 +
**[[Biting Flies#Psychodidae|sand fly]] bite
 +
 +
*Leishmaniasis in British dogs
 +
**Susceptible to infection if exposed whilst abroad in endemic areas as have no immunity
 +
**No [[Biting Flies#Psychodidae|sand flies]] in Britain but dogs have become infected whilst in contact with infected imported animals
 +
 +
'''Diagnosis'''
 +
*Demonstrate ''Leishmania'' organisms
 +
**In skin scraping or smears
 +
**In [[Lymph Nodes - Anatomy & Physiology|lymph node]] or [[Bone Marrow - Anatomy & Physiology|bone marrow]] biopsies
 +
 +
'''Treatment and Control'''
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*Chemotherapy
 +
**Prolonged treatment, expensive, suppresses infection
 +
**Does not cure infection
 +
 +
*Prevent [[Biting Flies#Psychodidae|sand flies]] biting
 +
**Collars, sprays containing [[Ectoparasiticides|insecticide]] with repellent effect
 +
 +
*Destruction of infected and stray dogs
 +
**[[Biting Flies#Psychodidae|Sand flies]] biting infected dogs may spread the disease to to other dogs, humans and wildlife
 +
**There is a slight possibility of transmission to humans by direct contact
    
==''Trypanosoma''==
 
==''Trypanosoma''==
Line 133: Line 212:  
**In sheep caused by ''T. melophagium''
 
**In sheep caused by ''T. melophagium''
 
**In cattle caused by ''T. theileri''
 
**In cattle caused by ''T. theileri''
  −
==''Leishmania''==
  −
[[Image:Leishmania Life Cycle.jpg|thumb|right|150px|Leishmania Life Cycle - Wikimedia Commons]]
  −
[[Image:Leishmania donovani.jpg|thumb|right|150px|''Leishmania donovani'' in bone marrow cell - Dr. L.L. Moore, Jr.]]
  −
[[Image:Leishmania tropica.jpg|right|thumb|150px|''L. tropica'' - Yutaka Tsutsumi, M.D., Professor, Department of Pathology, Fujita Health University School of Medicine]]
  −
*''Leishmania'' spp. are intracellular parasites of [[Macrophage|macrophages]]
  −
  −
*Are closely related to ''Trypanosoma'' spp.
  −
  −
*Cause diseases in humans, dogs and wild animals
  −
  −
*Present in southern Europe, Africa, Asia and South America
  −
  −
'''Life Cycle'''
  −
*Transmitted by blood sucking [[Biting Flies#Psychodidae|sand flies]]
  −
**''Phlebotomus'' spp. in the Old World
  −
**''Lutzomyia'' spp. in the New World
  −
  −
*The amastigote (morphological form) in found in vertebrate [[Macrophage|macrophages]]
  −
  −
*Ingested by [[Biting Flies#Psychodidae|sand fly]] during feeding
  −
**Transforms in [[Insecta|insect]] gut
  −
  −
*Multiplies and migrates to [[Insecta|insect]] proboscis
  −
**Innoculated during feeding
  −
**Can be transmitted percutaneously if [[Biting Flies#Psychodidae|sand fly]] crushed on skin
  −
  −
*Invades [[Macrophage|macrophages]] and reverts to amastigote
  −
  −
'''Pathogenesis'''
  −
*Infection of vertebrate host
  −
**Produces foci of proliferating ''Leishmania''-infected [[Macrophage|macrophages]] in skin ('''cutaneous''') or internal organs ('''visceral''')
  −
  −
*Very long incubation periods
  −
**Months to years
  −
  −
*Many infected dogs are asymptomatic
  −
  −
*Cutaneous form
  −
**Produces areas of ulceration on pinnae of ears
  −
  −
*Visceral form causes chronic wasting condition
  −
**Generalised eczema
  −
***Loss of hair around eyes producing 'spectacle' effect
  −
**Intermittent fever
  −
**Generalised lymphadenopathy
  −
  −
*Involved in [[Parasitic skin infections - Pathology#Protozoa|skin infections]]
  −
  −
'''Epidemiology'''
  −
*Disease dependent on [[Biting Flies#Psychodidae|sand fly]] vectors
  −
**E.g. Common in dogs around the Mediterranean coast, foci around southern Europe and around Madrid
  −
  −
*Reservoirs of infection
  −
**E.g. Wild animals such as rodents and stray dogs
  −
  −
*Mechanisms of transmission
  −
**Direct contact
  −
**[[Biting Flies#Psychodidae|sand fly]] bite
  −
  −
*Leishmaniasis in British dogs
  −
**Susceptible to infection if exposed whilst abroad in endemic areas as have no immunity
  −
**No [[Biting Flies#Psychodidae|sand flies]] in Britain but dogs have become infected whilst in contact with infected imported animals
  −
  −
'''Diagnosis'''
  −
*Demonstrate ''Leishmania'' organisms
  −
**In skin scraping or smears
  −
**In [[Lymph Nodes - Anatomy & Physiology|lymph node]] or [[Bone Marrow - Anatomy & Physiology|bone marrow]] biopsies
  −
  −
'''Treatment and Control'''
  −
*Chemotherapy
  −
**Prolonged treatment, expensive, suppresses infection
  −
**Does not cure infection
  −
  −
*Prevent [[Biting Flies#Psychodidae|sand flies]] biting
  −
**Collars, sprays containing [[Ectoparasiticides|insecticide]] with repellent effect
  −
  −
*Destruction of infected and stray dogs
  −
**[[Biting Flies#Psychodidae|Sand flies]] biting infected dogs may spread the disease to to other dogs, humans and wildlife
  −
**There is a slight possibility of transmission to humans by direct contact
 
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