CAMPY

Understanding  pathogenicity, epidemiology and  antimicrobial resistance  of  Campylobacter jejuni  and  coli,  significant  foodborne pathogens 

Consortium Leader:  Professor Marja-Liisa Hänninen, University of Helsinki, Department of Food and Environmental Hygiene (www.helsinki.fi)

Other group leaders:
Docent Hilpi Rautelin, University of Helsinki, Haartman Institute, Department of Bacteriology and Immunology (www.helsinki.fi)

Other persons involved in the project:
LK Benjamin Feodoroff
FM Kerttu Valtanen
FM Elli Tervonen
DI Rauni Kärenlampi

ABSTRACT  

Campylobacter jejuni and coli are the most common bacterial enteropathogens in Finland. During the last years the number of annually reported cases has been at level 3500 - 4000. Although majority of the cases are acquired during travel abroad a high number of the patients acquire the infection from domestic sources as well, especially during the summer peak. Campylobacter infections are food- or waterborne. Only little is known about the pathogenicity of campylobacters. Also the relative significance of various potential sources remains unknown. Our aim is to study with modern molecular methods pathogenicity, epidemiology and antimicrobial resistance in C. jejuni and C. coli.

The basic knowledge on molecular epidemiology and population biology of Campylobacter will be obtained by analysis of isolates from patients, various animal reservoirs, foods, water and wild birds from 1996 to 2010. Multi-Locus Sequence Typing (MLST) will be used for population genetic analysis studying potential changes in populations in various hosts and their associations with changes in populations infecting humans. Similarly, the results can be used for studies on potential host-adapted types. A more discriminatory analysis of the strains will be obtained by pulsed-field gel electrophoresis (PFGE). Differences in virulence are studied by both gene-specific techniques as well as genome-wide analysis using well-characterized strains from our collection and new genomic data. Adaptation to a wide variety of hosts and environmental survival are the key factors in the epidemiology of Campylobacter infections. Adatation and adaptation mechanisms are studied by application of genome-wide data and proteomics. A specific example of adaptation is evolvement and acquisition of antimicrobial resistance. Mechanisms in the evolvement and persistence of resistance/multiresistance are studied at target-gene as well as unspecific level. Results of our studies will be used for better understanding of the epidemiology of Campylobacter infections, importance of host adaptation/selection in colonisation and bacterial factors controlling virulence and pathogenicity and development of approaches for prevention of evolvement of antimicrobial resistance in Campylobacter.  

Key words:  Campylobacter, pathogenicity, epidemiology, antimicrobial resistance