Difference between revisions of "Campylobacter species"
Jump to navigation
Jump to search
| Line 1: | Line 1: | ||
<big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big> | <big><center>[[Infectious agents and parasites|'''BACK TO INFECTIOUS AGENTS AND PARASITES''']]</center></big> | ||
<big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big> | <big><center>[[Bacteria|'''BACK TO BACTERIA''']]</center></big> | ||
| − | + | ||
| − | |||
* Linked to: | * Linked to: | ||
| Line 27: | Line 26: | ||
*Non-thermophilic species e.g. ''C. fetus'' | *Non-thermophilic species e.g. ''C. fetus'' | ||
*Grow on enriched media e.g. Skirrow agar in 1-10% carbon dioxide and 5-10% oxygen tension | *Grow on enriched media e.g. Skirrow agar in 1-10% carbon dioxide and 5-10% oxygen tension | ||
| + | *''C. jejuni'' requires increased temperatures for growth | ||
*Many grow on MacConkey | *Many grow on MacConkey | ||
*Oxidase positive, non-fermentative | *Oxidase positive, non-fermentative | ||
| Line 36: | Line 36: | ||
*''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 | *''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 | ||
| + | *Antigens of S layer undergoes antigenic shifts in ''C. fetus'' subspecies ''venerealis'', allowing persistence in the host | ||
*''C. jejuni'' attaches and invades host enterocytes and produces enterotoxin-like substances | *''C. jejuni'' attaches and invades host enterocytes and produces enterotoxin-like substances | ||
| Line 41: | Line 42: | ||
===Clinical infections=== | ===Clinical infections=== | ||
| + | *''Campylobacter fetus'' subspecies ''venerealis'' | ||
| + | **Venereal infection of cattle | ||
| + | **Infertility in female cattle | ||
| + | **Found in glandular crypts of prepuce of bull with no clinical signs - carriers | ||
| + | **Causes catarrhal inflammation in female genital tract | ||
| + | **Endometritis prevents implantation until infection gone and causes early embryonic death, occasionally sporadic abortion | ||
| + | **May remain infertile for 3-5 months before immunity develops, which lasts 4-5 years | ||
| + | **Effective immunity includes induction of IgA in the vagina and IgG in the uterus | ||
| + | **Bacteria may persist in the vagina and be transmitted to bulls | ||
===Diagnosis=== | ===Diagnosis=== | ||
| + | *Smears stained with dilute carbol fuschin for 4 minutes | ||
Revision as of 07:47, 18 May 2008
- Linked to:
- Undifferentiated neonatal calf diarrhoea, a mixed viral enteritis in calves.
- Food poisoning (Campylobacter jejuni).
Overview
- Live on mucosa of intestinal and genital tract and can be commensals or pathogens
- Enteric species cause disease in humans
- Other species cause infertility and abortion in cattle and sheep
- Excreted in faeces of birds, (C. jejuni and C. lari) as well as pigs contaminating water and food supplies
- C. fetus restricted to bovine prepucial mucosa
Characteristics
- Curved, Gram negative rods
- Polar flagellum aids motility
- Daughter cells remain joined giving gull-wing or spiral appearance
- Microaerophilic
- Sensitive to drying
- Thermophilic species - C. jejuni, C. coli
- Non-thermophilic species e.g. C. fetus
- Grow on enriched media e.g. Skirrow agar in 1-10% carbon dioxide and 5-10% oxygen tension
- C. jejuni requires increased temperatures for growth
- Many grow on MacConkey
- Oxidase positive, non-fermentative
- C. fetus subspecies venerealis and subspecies fetus have small, round, smooth, translucent colonies
- C. jejuni has small, flat, grey colonies with watery appearance
Pathogenesis and pathogenicity
- 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
- Antigens of S layer undergoes antigenic shifts in C. fetus subspecies venerealis, allowing persistence in the host
- C. jejuni attaches and invades host enterocytes and produces enterotoxin-like substances
Clinical infections
- Campylobacter fetus subspecies venerealis
- Venereal infection of cattle
- Infertility in female cattle
- Found in glandular crypts of prepuce of bull with no clinical signs - carriers
- Causes catarrhal inflammation in female genital tract
- Endometritis prevents implantation until infection gone and causes early embryonic death, occasionally sporadic abortion
- May remain infertile for 3-5 months before immunity develops, which lasts 4-5 years
- Effective immunity includes induction of IgA in the vagina and IgG in the uterus
- Bacteria may persist in the vagina and be transmitted to bulls
Diagnosis
- Smears stained with dilute carbol fuschin for 4 minutes