Difference between revisions of "Cryptosporidium"

Revision as of 15:34, 25 November 2008

PARASITES PROTOZOA

Recognition

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

Minute protozoan parasite

Wide host range

Parasitises epithelial cells lining the epithelial cells lining the ailimentary and respiratory tracts

Developmental stages confined to the microvillous brish border

C. parvum most associated with disease in domestic animals and in humans
- Other species affect birds

Small oocysts of 4-5μm

Life Cycle

Direct life cycle
- Only one host
- Homoxenous

1 week prepatent period

Sporulated oocysts past in faeces

Autoinfection can occur
- Thin walled oocysts

Faecal-oral transmission also occurs
- Thick walled oocysts

Pathogenesis

Causes outbreaks of diarrhoea in young animals

Common cause of calf-hood scours
- Older animals may be asymptomatic carriers
- Contributes to undifferentiated neonatal calf diarrhoea which is a mixed viral enteritis in calves

Common infection in AIDS patients

Epidemiology

Direct faecal-oral infection
- E.g. School parties visiting farms

Water-bourne 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 brought-in calves
- Treat if signs of diarrhoea present

Good hygiene, adequate bedding, disinfection of calf pens is important

Prevention/treatment
- Halofuginone
  - Halocur or Intervet
  - Oral dosage

@@ Line 1: / Line 1: @@
-{{OpenPagesTop}}
+{{review}}
-{{Taxobox
-|kingdom            =Protista
+{{toplink
-|phylum             =Myzozoa
+|backcolour =
-|class              =[[:Category:Coccidia|Coccidea]]
+|linkpage =Parasites
-|sub-class          =
+|linktext =PARASITES
-|order              =Eucoccidiorida
+|pagetype=Bugs
-|super-family       =
+|sublink1=Protozoa
-|family             =Cryptosporidiidae
+|subtext1=PROTOZOA
-|sub-family         =
-|genus              =Cryptosporidium
-|species            =''C. parvum'' and more
 }}
+<br>
-==Overview==
+==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 muris.jpg|thumb|right|150px|''C. muris'' - Wikimedia Commons]]
-[[Image:Cryptosporidium Life Cycle.jpg|thumb|right|150px|''Cryptosporidium Life Cycle'' - Alexander J. da Silva et al., 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: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.
+*Minute protozoan parasite
+*Wide host range
+*Parasitises epithelial cells lining the epithelial cells lining the ailimentary and respiratory tracts
+*Developmental stages confined to the '''microvillous brish 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==
-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.
+*Direct life cycle
+**Only one host
+**Homoxenous
+*1 week prepatent period
+*'''Sporulated''' oocysts past in faeces
+*Autoinfection can occur
+**Thin walled oocysts
+*Faecal-oral transmission also occurs
+**Thick walled oocysts
 ==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 [[Intestine Diarrhoea - Pathology|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 [[Intestines Catarrhal Enteritis - Pathology#Undifferentiated Neonatal Calf Diarrhoea|undifferentiated neonatal calf diarrhoea]] which is a mixed viral enteritis in calves
+*Common infection in AIDS patients
 ==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-bourne 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 brought-in calves
+**Treat if signs of [[Intestine Diarrhoea - Pathology|diarrhoea]] present
-{{review}}
+*Good hygiene, adequate bedding, disinfection of calf pens is important
-{{OpenPages}}
+*Prevention/treatment
-[[Category:Enteritis,_Parasitic]]
+**Halofuginone
-[[Category:Enteritis,_Villus_Atrophy]]
+***Halocur or Intervet
-[[Category:Expert_Review]]
+***Oral dosage
-[[Category:Coccidia]]