Difference between revisions of "Babesia"

From WikiVet English
Jump to navigation Jump to search
(20 intermediate revisions by 5 users not shown)
Line 1: Line 1:
== Epidemiology ==
+
[[Image:Babesia Life Cycle.jpg|thumb|right|150px|''Babesia'' Life Cycle Diagram - Dennis Jacobs & Mark Fox RVC]]
 +
[[Image:Alternative Babesia life cycle diagram.jpg|thumb|right|150px|''Babesia'' Life Cycle - Mariana Ruiz Villarreal]]
 
*Infects a wide range of host species in different areas of the world
 
*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. First of all, it prevents European breeds from being successful in tropical regions where [[Ticks|ticks]] are endemic as well as occurring sporadically in the UK and Ireland causing losses of around £8 million per year.
+
*Babesiosis has severe effects on cattle production in parts of the world
 +
**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''' ===
+
'''Life Cycle'''
Both [[Ticks#Disease Transmission|trans-stadial]] and [[Ticks#Disease Transmission|trans-ovarian]] transmission occurs with each female [[Ticks|tick]] producing 3000 eggs and the [[Ticks|tick]] being the definitive host.
+
*Both [[Ticks#Disease Transmission|trans-stadial]] and [[Ticks#Disease Transmission|trans-ovarian]] transmission occurs
  
''Babesia'' multiplies in the red blood cells by '''budding''' and it forms 2-4 daughter cells (species dependent).
+
*Each female [[Ticks|tick]] produces 3000 eggs
Giemsa blood smears can differentiate between species using 'Difquik' stain.
+
 
 +
*The [[Ticks|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
 
*''Babesia'' species are either small or large depending on the size of the daughter cells
Line 28: Line 36:
  
 
*Antigen is released which adsorbs onto other red blood cells
 
*Antigen is released which adsorbs onto other red blood cells
**Causes haemolysis and [[Pigmentation - Pathology#Haemoglobin|haemoglobin pigmentation]]
+
**Causes haemolysis and [[Pigmentation and Calcification - Pathology#Haemoglobin|haemoglobin pigmentation]]
 
**Causes haemolytic anaemia, haemoglobinuria and fever
 
**Causes haemolytic anaemia, haemoglobinuria and fever
  
Line 54: Line 62:
  
 
*'''Lower''' incidence of disease
 
*'''Lower''' incidence of disease
 
  
  
 
<big>'''[[Babesiosis - Cattle|Cattle Babesiosis]]
 
<big>'''[[Babesiosis - Cattle|Cattle Babesiosis]]
  
'''[[Babesia canis]]'''
 
  
'''[[Babesiosis - Horse|Horse 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
 +
****[[Hard Ticks - Overseas|''Dermacentor'']] vector
 +
****Largely confined to southern Europe but is spreading
 +
***''B. canis'' uses [[Hard Ticks - Overseas|''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 [[Ticks|tick]] bites by use of an 'Amitraz' collar is currently the best method of protection
  
'''[[Babesiosis - Small Ruminants|Sheep and Goat Babesiosis]]
+
*Horses
</big>
+
**2 species occur
 +
**''B. equi'' is the most pathogenic
 +
**Not endemic to the UK
 +
**Serology using ELISA or IFAT to diagnose
  
*''Babesia bovis'' myositis
+
*Sheep and goats
**In cattle
+
**Several species
**Infrequent muscle [[Muscle Necrosis|necrosis]]
+
**Little clinical significance
  
==Test yourself with the Piroplasmida Flashcards==
 
 
[[Piroplasmida_Flashcards|Piroplasmida Flashcards]]
 
  
 
[[Category:Piroplasmida]]
 
[[Category:Piroplasmida]]
 
[[Category:To_Do_-_Parasites]]
 

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