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#REDIRECT[[:Category:Campylobacter species]]
 
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|backcolour =
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|linkpage =Bacteria
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|linktext =BACTERIA
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|pagetype=Bugs
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<br>
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===Overview===
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*Live on mucosa of intestinal and genital tract and can be commensals or pathogens
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*Enteric species cause disease in humans
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*Other species cause infertility and abortion in cattle and sheep
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*Excreted in faeces of birds, (''C. jejuni'' and ''C. lari'') as well as pigs contaminating water and food supplies
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*''C. fetus'' restricted to bovine prepucial mucosa
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===Characteristics===
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*Curved, Gram negative rods
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*Polar flagellum aids motility
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*Daughter cells remain joined giving gull-wing or spiral appearance
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*Microaerophilic
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*Sensitive to drying
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*Thermophilic species - ''C. jejuni, C. coli''
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*Non-thermophilic species e.g. ''C. fetus''
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*Grow on enriched selective media e.g. Skirrow agar in 1-10% carbon dioxide and 5-10% oxygen tension
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*''C. jejuni'' requires increased temperatures for growth
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*Many grow on MacConkey
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*Oxidase positive, non-fermentative
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*''C. fetus'' subspecies ''venerealis'' and subspecies ''fetus'' have small, round, smooth, translucent colonies
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*''C. jejuni'' has small, flat, grey colonies with watery appearance
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*Smears stained with dilute carbol fuschin for 4 minutes
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===Pathogenesis and pathogenicity===
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*''C. fetus'' subspecies ''fetus'' and subspecies ''venerealis'' possess a microcapsule (S layer) which resists phagocytosis and serum-mediated destruction and enhances survival in the genital tract
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*Antigens of S layer undergoes antigenic shifts in ''C. fetus'' subspecies ''venerealis'', allowing persistence in the host
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*''C. jejuni'' attaches and invades host enterocytes and produces enterotoxin-like substances
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*Flagellae of ''C. jejuni'' required for colonisation
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===''Campylobacter fetus'' subspecies ''venerealis''===
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*Venereal infection of cattle
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*Infertility in female cattle
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*Found in glandular crypts of prepuce of bull with no clinical signs - carriers
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*Causes catarrhal inflammation in female genital tract
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*Endometritis prevents implantation until infection cleared and causes early embryonic death, occasionally sporadic abortion
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*May remain infertile for 3-5 months before immunity develops, which lasts 4-5 years
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*Effective immunity includes induction of IgA in the vagina and IgG in the uterus
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*Bacteria may persist in the vagina and be transmitted to bulls
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*Diagnosis:
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**Fluorescent antibody test on genital discharges from bull/cow
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**Vaginal mucus agglutination test
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**ELISA to IgA antibodies in vaginal mucus after an abortion
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**PCR for detection in semen
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*Treatment: dihydrostreptomycin intrauterine for cows and systemically or topically for bulls
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*Vaccination: bacterin in oil adjuvant
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===''Campylobacter fetus'' subspecies ''fetus''===
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*Sporadic abortion in cows and sheep
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*10% of ovine abortions in the UK
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*Enteric organism of sheep, goats and cattle; faecal-oral transmission
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*Ingestion during last trimester of pregnancy causes a bacteraemia
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*Bacteria reach the uterus
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*Necrotic placentitis causes late abortion, still birth or weak lambs
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*Sporadic abortion in cattle
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*Aborted lambs may have round necrotic lesions on surface of liver
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*Aborting ewes source of infection for vulnerable animals
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*Up to 20% of flock may abort
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*Solid immunity developed
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*S layer immunodominant antigen
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*Diagnosis: hepatic lesions in lambs; presence of organisms in foetal abomasum; isolation and identification
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*Treatment/control: isolate aborting ewes; destroy placenta; move other ewes to clean pasture; vaccinate flock with bacterin during outbreak and prophylactically; chlortetracycline in feed in an outbreak
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===[[Intestine Pathogens - Pathology#Campylobacter jejuni|''Campylobacter jejuni'']]===
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*Widespread on farms - hyperendemic
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*Carried as commensals in intestines of cattle, sheep, dogs, wild birds and especially chickens
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*Farm animals regularly exposed via faecal-oral route; maternal antibody protects while active immunity develops
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*Animals with little exposure are very susceptible, e.g. humans, pets
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*Most chicken carcasses contaminated, leading to food poisoning and enterocolitis in people from uncooked meat
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*Colonisation, attachment and invasion of colonic enterocytes; toxin production
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*Necrosis of colonic absorptive epithelial cells, erosion of mucosa, crypt abscesses, inflammatory infiltrate of [[Neutrophils - WikiBlood|neutrophils]] into mucosa causes colitis
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*Enteritis and diarrhoea in susceptible dogs; treatment with enrofloxacin
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*Causes abortion in ewes
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*Usually asymptomatic infections in chickens and turkeys, but occasional outbreaks of avian hepatitis occur with decreased egg production, loss of condition, haemorrhage and necrosis of liver; phase contrast microscopy demonstrates curved rods in bile; in-feed dihydrostreptomycin sulphate in outbreak
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*Implicated in [[Intestines Catarrhal Enteritis - Pathology#Undifferentiated Neonatal Calf Diarrhoea|undifferentiated neonatal calf diarrhoea]], a mixed viral enteritis in calves
 
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