Tracing and quantitative detection of Campylobacter jejuni

• Forschungsstelle: BLV
• Projektnummer: 1.08.12
• Projekttitel Englisch: Tracing and quantitative detection of Campylobacter jejuni

Schlüsselwörter (Englisch)

Epidemiology, tracing, monitoring, host-specificity

Kurzbeschreibung (Englisch)

Infection with Campylobacter has become the major cause for bacterial enteritis in Europe and other parts of the developed world, overtaking Salmonella. Campylobacter jejuni accounts for approximately 80-85% of cases whereas Campylobacter coli is causing about 10-15% of infections. Due to the fact that Campylobacter are mostly commensal in the enteron of many warm-blooded animals used for meat production, Campylo-bacter enteritis is a zoonotic disease. Quality control, monitoring and eventually tracing of contaminated food products is therefore important for public health concerns. Typing of Campylobacter is used for this purpose and the Multi-Locus-Sequence-Typing (MLST) using 7 house-keeping genes has become the method of choice these days. We recently developed a rapid and cost-efficient multiplexing strategy which allows MLST on C. jejuni and C. coli in a routine way. This tool shall now be applied with currently isolated C. jejuni strains from human and poultry in order to get information on circulating strains of zoonotic relevance. In the main task of the project a real-time PCR assay for detection and enumeration of C. jejuni will be developed. For this purpose appropriate targets have to be defined which ideally could also be used to get information on the host origin of the detected strains, thereby providing important epidemiological insights. Direct application of the MLST method as well as the real-time PCR on primary material (food, animal samples, carcasses, etc.) instead of isolated bacterial strains will be evaluated, what could improve the overall speed for identification and typing. All data will be collected and managed in a comprehensive Bionumerics database. The data and methods generated within this project will improve diagnostics and epidemiological knowledge of Campylo-bacter and provide support for intervention measures to contain or even prevent outbreaks.

Projektziele (Englisch)

There are four objectives:

• develop a real-time PCR for the detection and quantification of C. jejuni
• apply the optimized MLST method with currently isolated C. jejuni strains and eventually adapt the MLST method for direct typing from food and other samples
• define host-specific markergene(s) for tracing C. jejuni eventually use it for real-time PCR
• maintenance and running of the Bionumerics containing epidemiological data

Umsetzung und Anwendungen (Deutsch)

31.05.2007:  Umsetzung:
Datenbank für Ursprungsabklärungen
Empfehlungen an Konsumenten
Grundlagen zur Risikoabschätzung
Erkenntnisse zu Überwachungsprioritäten
Know-how für Datenbankbetreuung (Selektionssitzung 2007/mvo)

Umsetzung und Anwendungen (Englisch)

MLST is nowadays an established method for C. jejuni typing even though many other, less robust and more time-consuming methods are still used (PFGE, fla-RFLP, AFLP). Therefore, we are in a good position to apply the recently established and optimized MLST method on currently isolated C. jejuni strains. The data will improve the monitoring of C. jejuni and also allow an international collaboration, exchange and comparison of data. Including a method that will allow host species association with types of C. jejuni will significantly improve the traceability of this zoonotic pathogen

The quantification of C. jejuni is becoming necessary information and the reference laboratory at the ZOBA has a need for such a method. The Bionumerics database which has been established during former projects and which has been reactivated during the preceding C. jejuni project (1.06.04) has to be kept up to date and maintained. This is not possible without a person with the necessary know-how. The presented project is therefore a way to keep this valuable database running without loosing data and information generated in the framework of various former projects. A long-term solution and appropriate finances for the maintenance of the database has to be found which could be done by an informatics of the ZOBA.

Publikationen / Ergebnisse (Englisch)

Wirz, S.E.; Overesch, G.; Kuhnert, P.; Korczak, B.M. (2010) Genotype and antibiotic resistance analysis of Campylobacter isolates from caeca and the carcasses of slaughtered broiler flocks. Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of CH-3001 Bern, Switzerland.

Schnider, A.; Overesch, G.; Korczak, B.M.; Kuhnert, P. Comparison of Real-Time PCR Assays for Detection, Quantification, and Differentiation of Campylobacter jejuni and Campylobacter coli in Broiler Neck Skin Samples3. Journal of Food Protection, Vol. 73, No. 6, 2010, Pages 1057–1063. Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of CH-3001 Bern, Bern, Switzerland.

Schnider, A. (2009) Prevalence of Campylobacter jejuni and Campylobacter coli on Swiss broiler carcasses determined by comparative real-time PCR. Inaugural-Dissertation, Vetsuisse-Fakultät, Universität Bern.

Schnider, A. et al. (2010) Comparison of real-time PCR assays for detection, quantification, and differentiation of Campylobacter jejuni and Campylobacter coli in broiler neck skin samples. J.Food Prot. 73:1057-1063.

Wirz, S. (2009) Genotypes and antibiotic resistance of Campylobacter isolates from Swiss broiler during 2008. Inaugural-Dissertation, Vetsuisse-Fakultät, Universität Bern.

Wirz, S.; Overesch, G.; Kuhnert, P.; Korczak, B.M. (2010) Genotype and antibiotic resistance analysis of Campylobacter isolates from caeca and the carcasses of slaughtered broiler flocks. Appl.Environ.Microbiol. in press.

Kittl, S. (2010) Comparison of genotypes and antibiotic resistance of Campylobacter jejuni from humans and slaughtered chickens in Switzerland. Inaugural-Dissertation, Vetsuisse-Fakultät, Universität Bern.

Zugehörige Dokumente

• 1.08.12 Datenblatt MJB2011,Kuhnert [PDF] 95 kB
• AEM.00813-10v1.pdf [PDF] 476 kB
• Campy_RT_PCR.pdf [PDF] 2'300 kB