Difference between revisions of "Babesia"

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[[Image:Babesia Life Cycle.jpg|thumb|right|150px|''Babesia'' Life Cycle Diagram - Dennis Jacobs & Mark Fox RVC]]
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[[Image:Alternative Babesia life cycle diagram.jpg|thumb|right|150px|''Babesia'' Life Cycle - Mariana Ruiz Villarreal]]
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*Infects a wide range of host species in different areas of the world
 +
 
 +
*Babesiosis has severe effects on cattle production in parts of the world
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**Prevents European breeds from being successful in tropical regions where [[Ticks|ticks]] are endemic.
 +
**Occurs sporadically in the UK and Ireland causing losses of around £8 million per year
 +
 
 +
'''Life Cycle'''
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*Both [[Ticks#Disease Transmission|trans-stadial]] and [[Ticks#Disease Transmission|trans-ovarian]] transmission occurs
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*Each female [[Ticks|tick]] produces 3000 eggs
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*The [[Ticks|tick]] is the definitive host
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*''Babesia'' multiplies in the red blood cells by '''budding'''
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**Forms 2-4 daughter cells (species dependent)
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**Giemsa blood smears can differentiate between species using 'Difquik' stain
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*''Babesia'' species are either small or large depending on the size of the daughter cells
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*Small ''Babesia''
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**E.g. ''B. divergens''
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**E.g. ''B. gibsoni''
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**Peripheral nucleus
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**Obtuse angle
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*Large ''Babesia''
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**E.g. ''B. major''
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**E.g. ''B. canis-complex''
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**Central nucleus
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**Acute angle
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*Daughter cells disrupt the red blood cell and are released
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**Spread and infect other red blood cells
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*Antigen is released which adsorbs onto other red blood cells
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**Causes haemolysis and [[Pigmentation and Calcification - Pathology#Haemoglobin|haemoglobin pigmentation]]
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**Causes haemolytic anaemia, haemoglobinuria and fever
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===Enzootic Instability===
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*Low rate of transmission
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*Few infected [[Ticks|ticks]]
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*Infrequent exposure
 +
 
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*Immunity wanes or is completely absent in many individuals
 +
 
 +
*Low levels of herd immunity
 +
 
 +
*'''Higher''' incidence of disease
 +
 
 +
===Enzootic Stability===
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*High rate of transmission
 +
 
 +
*Many infected ticks
 +
 
 +
*Frequent exposure boosts immunity
 +
 
 +
*High level of herd immunity
 +
 
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*'''Lower''' incidence of disease
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 +
 
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<big>'''[[Babesiosis - Cattle|Cattle Babesiosis]]
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*Dogs
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**Complex epidemiology
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**Recognised species are extending their endemic ranges due to the discovery of the small ''Babesia'' species, pet passport scheme and increased overseas travel
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**Large species comprises 3 subspecies
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***''B. canis canis'' is the most important
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****[[Hard Ticks - Overseas|''Dermacentor'']] vector
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****Largely confined to southern Europe but is spreading
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***''B. canis'' uses [[Hard Ticks - Overseas|''Rhipicephalus'']] as a vector and is spreading northwards through Europe
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***''B. gibsoni'' is now established in the USA and South-East Asia
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**British dogs have no immunity as no species are endemic to the UK so are highly susceptible if taken abroad
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**Prevention of [[Ticks|tick]] bites by use of an 'Amitraz' collar is currently the best method of protection
 +
 
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*Horses
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**2 species occur
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**''B. equi'' is the most pathogenic
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**Not endemic to the UK
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**Serology using ELISA or IFAT to diagnose
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 +
*Sheep and goats
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**Several species
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**Little clinical significance
 +
 
 +
 
 +
[[Category:Piroplasmida]]

Revision as of 22:21, 9 April 2010

Babesia Life Cycle Diagram - Dennis Jacobs & Mark Fox RVC
Babesia Life Cycle - Mariana Ruiz Villarreal
  • Infects a wide range of host species in different areas of the world
  • Babesiosis has severe effects on cattle production in parts of the world
    • Prevents European breeds from being successful in tropical regions where ticks are endemic.
    • Occurs sporadically in the UK and Ireland causing losses of around £8 million per year

Life Cycle

  • Each female tick produces 3000 eggs
  • The tick is the definitive host
  • Babesia multiplies in the red blood cells by budding
    • Forms 2-4 daughter cells (species dependent)
    • Giemsa blood smears can differentiate between species using 'Difquik' stain
  • Babesia species are either small or large depending on the size of the daughter cells
  • Small Babesia
    • E.g. B. divergens
    • E.g. B. gibsoni
    • Peripheral nucleus
    • Obtuse angle
  • Large Babesia
    • E.g. B. major
    • E.g. B. canis-complex
    • Central nucleus
    • Acute angle
  • Daughter cells disrupt the red blood cell and are released
    • Spread and infect other red blood cells
  • Antigen is released which adsorbs onto other red blood cells

Enzootic Instability

  • Low rate of transmission
  • Infrequent exposure
  • Immunity wanes or is completely absent in many individuals
  • Low levels of herd immunity
  • Higher incidence of disease

Enzootic Stability

  • High rate of transmission
  • Many infected ticks
  • Frequent exposure boosts immunity
  • High level of herd immunity
  • Lower incidence of disease


Cattle Babesiosis


  • Dogs
    • Complex epidemiology
    • Recognised species are extending their endemic ranges due to the discovery of the small Babesia species, pet passport scheme and increased overseas travel
    • Large species comprises 3 subspecies
      • B. canis canis is the most important
        • Dermacentor vector
        • Largely confined to southern Europe but is spreading
      • B. canis uses Rhipicephalus as a vector and is spreading northwards through Europe
      • B. gibsoni is now established in the USA and South-East Asia
    • British dogs have no immunity as no species are endemic to the UK so are highly susceptible if taken abroad
    • Prevention of tick bites by use of an 'Amitraz' collar is currently the best method of protection
  • Horses
    • 2 species occur
    • B. equi is the most pathogenic
    • Not endemic to the UK
    • Serology using ELISA or IFAT to diagnose
  • Sheep and goats
    • Several species
    • Little clinical significance
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