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| − | <big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big>
| + | #REDIRECT[[:Category:Campylobacter species]] |
| − | <big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big>
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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 gone 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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| − | ===[[Intestines - disease due to pathogens#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 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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