Eurosurveillance - Volume 8, Issue 11, 01 November 2003

Two surveys have been conducted on behalf of the Campylobacter Working Group with the aim of assessing the feasibility of a European network on human Campylobacter infections. The first survey, conducted in 18 countries, collected information about diagnostic methods used for surveillance purpose while the second one, conducted among 10 European countries, gathered data on diagnostic methods and procedures in primary laboratories. Seventeen of the 18 countries had a surveillance system for Campylobacter infections and 13 a national reference laboratory. The case definition used for the surveillance in all these countries included laboratory confirmation. No commonly applicable subtyping methods were applied. Concerning primary laboratories dealing with Campylobacter infections, only a few of them reported directly to the national level, and antimicrobial susceptibility testing was performed by about half of the laboratories. These surveys indicated that a basic infrastructure for a wide European Campylobacter surveillance exists.

The frequency of Campylobacter infections in humans, their potential severity, and the existence of preventive measures justify the implementation of a surveillance system for these infections. Before the implementation of the surveillance system, a survey of the Campylobacter diagnostic practices in the laboratories was performed. In the laboratories that responded, most investigated for Campylobacter at least once in 1999. Identification of the Campylobacter species was carried out by 86% of hospital laboratories and 37% of private laboratories. Antibiotic sensitivity tests were carried out by 75% and 32% of them respectively. Many laboratories test for Campylobacter in stool samples using comparable methods showing the feasibility of a surveillance system.

In 2001, one year after the study of microbiological laboratories that showed the feasibility of a surveillance of Campylobacter infections, 1389 private laboratories were asked whether they would be willing to participate. The high proportion of positive responses (48%, 661) allowed the implementation on 1 April 2002 of surveillance of human Campylobacter infections.

Over 700 participants from 54 countries attended the eleventh Campylobacter, Helicobacter and Related Organisms (CHRO) meeting in September 2001. This meeting was an opportunity to update and better understand the microbiological and epidemiological complexities of Campylobacter. The mechanism of pathogenesis of this bacteria is not yet fully understood and important progress was made in the microbiological characterisation. The availibility of over 100 different strain characteristics from various locations all over Europe, brought together by Campynet, is an invaluable tool for achieving this aim. There is increasing evidence to suggest that different risk factors exist for different species of Campylobacter. The link between antibiotic use in farm animals and increased resistance to some antimicrobials for humans still needs to be proved and some contradictory results reported on this issue.

Phenotypic and genetic characteristics of 21 strains of Salmonella serotype Heidelberg isolated in the years 1999 - 2003 from different sources in Italy were studied. Susceptibility patterns, plasmid analysis, and PFGE were used as epidemiological markers. Although non-homogeneous drug resistance patterns and plasmid profiles had been detected, PFGE patterns suggest the hypothesis of a nationwide clonal spread of this serotype associated with poultry.