Difference between revisions of "Cryptosporidium"

From WikiVet English
Jump to navigation Jump to search
(25 intermediate revisions by 3 users not shown)
Line 1: Line 1:
{{OpenPagesTop}}
+
{{unfinished}}
{{Taxobox
 
|kingdom            =Protista
 
|phylum            =Myzozoa
 
|class              =[[:Category:Coccidia|Coccidea]]
 
|sub-class          =
 
|order              =Eucoccidiorida
 
|super-family      =
 
|family            =Cryptosporidiidae
 
|sub-family        =
 
|genus              =Cryptosporidium
 
|species            =''C. parvum'' and more
 
}}
 
  
 
==Overview==
 
==Overview==
 +
Cryptosporidium is the single genus in the cryptosporidiidae family and contains at least 13 recognised species. These small protozoan parasites are able to infect a wide range of hosts including mammals, birds, reptiles and fish.
 +
 +
 +
 +
==Recognition==
 
[[Image:Cryptosporidium parvum.jpg|thumb|right|150px|''Cryptosporidium parvum'' - Courtesy of the Laboratory of Parasitology, University of Pennsylvania School of Veterinary Medicine]]
 
[[Image:Cryptosporidium parvum.jpg|thumb|right|150px|''Cryptosporidium parvum'' - Courtesy of the Laboratory of Parasitology, University of Pennsylvania School of Veterinary Medicine]]
[[Image:Cryptosporidium Life Cycle.jpg|thumb|right|150px|''Cryptosporidium Life Cycle'' - Alexander J. da Silva et al., WikiMedia Commons]]
+
[[Image:Cryptosporidium muris.jpg|thumb|right|150px|''C. muris'' - Wikimedia Commons]]
 +
[[Image:Cryptosporidium Life Cycle.jpg|thumb|right|150px|''Cryptosporidium'' Life Cycle - Alexander J. da Silva, PhD/Melanie Moser (PHIL #3386), 2002]]
 
[[Image:Calf.jpg|thumb|right|150px|Calf - nabrown RVC]]
 
[[Image:Calf.jpg|thumb|right|150px|Calf - nabrown RVC]]
 
[[Image:Cryptosporidium ruminant.jpg|thumb|right|150px|Ruminant ''Cryptosporidium'' - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona]]
 
[[Image:Cryptosporidium ruminant.jpg|thumb|right|150px|Ruminant ''Cryptosporidium'' - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona]]
Cryptosporidium is the single genus in the Cryptosporidiidae family and contains at least 13 recognised species. These small [[:Category:Protozoa|protozoan]] parasites are able to infect a wide range of hosts including mammals, birds, reptiles and fish. These species are the causative agents of [[cryptosporidiosis]], ''C. parvum'' is the most common species infecting mammals and man.
+
Cryptosporidium species are extremely small in size
 +
 
 +
*Parasitises epithelial cells lining the alimentary and respiratory tracts
 +
 
 +
*Developmental stages confined to the '''microvillous brush border'''
  
==Recognition==
+
*''C. parvum'' most associated with disease in domestic animals and in humans
 +
**Other species affect birds
  
Cryptosporidium species are extremely small in size, the oocysts being 4-5μm. They parasitise the epithelial cells lining the alimentary and respiratory tracts of the host. The developmental stages of the parasite are confined to the brush border area of the gut epithelium.
+
*Small oocysts of 4-5μm
  
 
==Life Cycle==
 
==Life Cycle==
Cryptosporidium mostly has a standard [[Coccidia Life Cycle|coccidial life cycle]] with a few exceptions. The oocyte does not contain sporocysts, instead the four sporozoites are free within the oocyst. Also the parasite does not invade the cells of the host, instead it develops in a membrane derived from the microvilli of the gut. The pre patent period of cryptosporidium is 1 week, after which '''sporulated''' oocysts are shed in the hosts faeces.
+
Cryptosporidium mostly has a standard [[Coccidia Life Cycle|coccidial life cycle]] with a few exceptions. The oocyte does not contain sporocysts, instead the sporozoites are free within the oocyst. The pre patent period of of cryptosporidium is 1 week, after which '''sporulated''' oocysts are shed in the hosts faeces.
  
 
==Pathogenesis==
 
==Pathogenesis==
  
In young calves ''Crytosporidium'' infection causes outbreak of severe [[Diarrhoea|diarrhoea]] or scour. Contributes to [[Undifferentiated Neonatal Calf Diarrhoea|undifferentiated neonatal calf diarrhoea]] which is a mixed viral enteritis in calves. Although it can cause severe illness in young animals, many older animals can be asymptomatic carriers of the disease.
+
*Causes outbreaks of [[Diarrhoea|diarrhoea]] in young animals
  
''Cryptosporidium'' is a '''zoonotic''' disease that can infect humans causing severe vomiting and diarrhoea. This is commonly seen in people who work with animals and do not practice sufficient hygiene and in AIDS and other immunocompromised patients.
+
*Common cause of calf-hood scours
 +
**Older animals may be asymptomatic carriers
 +
**Contributes to [[Calf Diarrhoea, Undifferentiated Neonatal|undifferentiated neonatal calf diarrhoea]] which is a mixed viral enteritis in calves
 +
 
 +
*Common infection in AIDS patients
  
 
==Epidemiology==
 
==Epidemiology==
Cryptosporidum can be transferred by two different routes;
 
*'''Faecal-oral infection'''
 
This involves ingestion of the sporulated oocysts, usually along with the ingestion of a small amount of fecal material. This can be due to grazing on common pasture as infected animals, meaning infections spread rapidly throughout young stock. In the case of zoonoses, this route is usually the result of poor hygiene after being in contact with potentially infected animals and their faeces. Washing and disinfecting hands after contact with young cattle can help prevent zoonotic infection.
 
*'''Water-borne infection'''
 
Contamination of the water supply can infect large numbers of people using a common water source. The source of this contamination is often difficult to locate.
 
  
{{Learning
+
*Direct faecal-oral infection
|flashcards = [[Cryptosporidia Flashcards]]
+
**E.g. School parties visiting farms
|literature search = [http://www.cabdirect.org/search.html?q=%28%28od%3A%28dogs%29%29%29+AND+%28%28title%3A%28%22Cryptosporidium%22%29%29%29 ''Cryptosporidium'' in dogs publications]<br>
+
 
[http://www.cabdirect.org/search.html?q=%28%28od%3A%28cats%29%29%29+AND+%28%28title%3A%28%22Cryptosporidium%22%29%29%29 ''Cryptosporidium'' in cats publications]<br>
+
*Water-borne infection
[http://www.cabdirect.org/search.html?q=%28%28od%3A%28horses%29%29%29+AND+%28%28title%3A%28%22Cryptosporidium%22%29%29%29 ''Cryptosporidium'' in horses publications]<br>
+
**E.g. contaminated water supply may infect hundreds of people
[http://www.cabdirect.org/search.html?rowId=1&options1=AND&q1=title%3A%28cryptosporidium%29+AND+od%3A%28cattle%29+&occuring1=freetext&rowId=2&options2=AND&q2=&occuring2=freetext&rowId=3&options3=AND&q3=&occuring3=freetext&publishedstart=2000&publishedend=yyyy&calendarInput=yyyy-mm-dd&la=any&it=any&show=all&x=58&y=9 ''Cryptosporidium'' in cattle publications since 2000]<br>
+
**Difficult to locate source
[http://www.cabdirect.org/search.html?q=%28%28od%3A%28sheep%29%29+AND+%28%28title%3A%28%22Cryptosporidium%22%29%29%29%29  ''Cryptosporidium'' in sheep publications]<br>
+
 
[http://www.cabdirect.org/search.html?q=%28od%3A%28goats%29%29+AND+%28%28title%3A%28%22Cryptosporidium%22%29%29%29 ''Cryptosporidium'' in goats publications]<br>
+
==Diagnosis==
[http://www.cabdirect.org/search.html?q=%28%28od%3A%28pigs%29%29+AND+%28%28title%3A%28%22Cryptosporidium%22%29%29%29%29 ''Cryptosporidium'' in pigs publications]
+
 
|full text = [http://www.cabi.org/cabdirect/FullTextPDF/2009/20093231161.pdf ''' Cryptosporidium and cryptosporidiosis: a brief review.''' Siddiki, A. M. A. M. Z.; Masuduzzaman, M.; Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria, Bulgarian Journal of Veterinary Medicine, 2009, 12, 2, pp 91-111, many ref.]<br>
+
*Faecal smear
[http://www.cabi.org/cabdirect/FullTextPDF/2007/20073017471.pdf ''' Cryptosporidiosis an important zoonotic disease: a review article.''' Roy, S. S.; Pramanik, A. K.; Subhasis Batabyal; Samar Sarkar; Pradeep Das; Intas Pharmaceuticals Ltd, Ahmedabad, India, Intas Polivet, 2006, 7, 2, pp 432-436, 26 ref.]<br>
+
**Ziehl-Neelson (ZN) stain
[http://www.cabi.org/cabdirect/FullTextPDF/2006/20063050537.pdf ''' Cryptosporidiosis: a review.''' Rashid, M.; Kotwal, S. K.; North-East Veterinarian, Guwahati, India, North-East Veterinarian, 2004, 4, 1, pp 25-27, 23 ref.]<br>
+
**Oocysts stain red against a blue/green background
[http://www.cabi.org/cabdirect/FullTextPDF/2005/20053163986.pdf ''' Cryptosporidiosis in dairy calves.''' Peregrine, A. S.; Leslie, K.; Trotz-Williams, L.; Ontario Veterinary Medical Association, Milton, Canada, Better medicine, better life. OVMA Conference Proceedings 2005, 2005, pp 185-189, 24 ref.]
+
 
|Vetstream = [https://www.vetstream.com/canis/search?s=protozoa Protozoa]
+
*Immunoassays
}}
+
**Detect oocysts in faeces
 +
 
 +
==Control==
 +
 
 +
*Isolate/quarantine bought-in calves
 +
**Treat if signs of [[Diarrhoea|diarrhoea]] present
 +
 
 +
*Good hygiene, adequate bedding and disinfection of calf pens is important
 +
 
 +
*Prevention/treatment
 +
**Halofuginone
 +
***Halocur or Intervet
 +
***Oral dosage
 +
 
 +
 
 +
==Villus Atrophy in Enteritis==
 +
 
 +
* Affects calf, lamb, piglet, kitten.  
 +
* Increasingly important as part of the neonatal [[Diarrhoea|diarrhoea]] complex in calves.  
 +
* Zoonosis.
 +
 
 +
====Pathology====
 +
 
 +
=====Gross=====
 +
 
 +
* Intestines diffusely reddened, with fluid contents.
 +
 
 +
=====Histological=====
  
 +
* Tiny parasites on surface of epithelium.
 +
* Villus atrophy and fusion.
 +
* Iinflammation (mainly lymphoid) in crypts and lamina propria.
  
{{review}}
+
<big>'''[[Cryptosporidia Flashcards]]</big>
  
{{OpenPages}}
+
[[Category:Miscellaneous_Protozoa]]
 
[[Category:Enteritis,_Parasitic]]
 
[[Category:Enteritis,_Parasitic]]
 
[[Category:Enteritis,_Villus_Atrophy]]
 
[[Category:Enteritis,_Villus_Atrophy]]
[[Category:Expert_Review]]
+
[[Category:To_Do_-_NickJ]]
 +
[[Category:To_Do_-_Parasites]]
 
[[Category:Coccidia]]
 
[[Category:Coccidia]]

Revision as of 14:55, 18 July 2010



Overview

Cryptosporidium is the single genus in the cryptosporidiidae family and contains at least 13 recognised species. These small protozoan parasites are able to infect a wide range of hosts including mammals, birds, reptiles and fish.


Recognition

Cryptosporidium parvum - Courtesy of the Laboratory of Parasitology, University of Pennsylvania School of Veterinary Medicine
C. muris - Wikimedia Commons
Cryptosporidium Life Cycle - Alexander J. da Silva, PhD/Melanie Moser (PHIL #3386), 2002
Calf - nabrown RVC
Ruminant Cryptosporidium - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona

Cryptosporidium species are extremely small in size

  • Parasitises epithelial cells lining the alimentary and respiratory tracts
  • Developmental stages confined to the microvillous brush border
  • C. parvum most associated with disease in domestic animals and in humans
    • Other species affect birds
  • Small oocysts of 4-5μm

Life Cycle

Cryptosporidium mostly has a standard coccidial life cycle with a few exceptions. The oocyte does not contain sporocysts, instead the sporozoites are free within the oocyst. The pre patent period of of cryptosporidium is 1 week, after which sporulated oocysts are shed in the hosts faeces.

Pathogenesis

  • Causes outbreaks of diarrhoea in young animals
  • Common infection in AIDS patients

Epidemiology

  • Direct faecal-oral infection
    • E.g. School parties visiting farms
  • Water-borne infection
    • E.g. contaminated water supply may infect hundreds of people
    • Difficult to locate source

Diagnosis

  • Faecal smear
    • Ziehl-Neelson (ZN) stain
    • Oocysts stain red against a blue/green background
  • Immunoassays
    • Detect oocysts in faeces

Control

  • Isolate/quarantine bought-in calves
  • Good hygiene, adequate bedding and disinfection of calf pens is important
  • Prevention/treatment
    • Halofuginone
      • Halocur or Intervet
      • Oral dosage


Villus Atrophy in Enteritis

  • Affects calf, lamb, piglet, kitten.
  • Increasingly important as part of the neonatal diarrhoea complex in calves.
  • Zoonosis.

Pathology

Gross
  • Intestines diffusely reddened, with fluid contents.
Histological
  • Tiny parasites on surface of epithelium.
  • Villus atrophy and fusion.
  • Iinflammation (mainly lymphoid) in crypts and lamina propria.

Cryptosporidia Flashcards