Worldwide, Campylobacter bacteria are associated with food-borne diseases. So far, while more than twenty species of Campylobacter have been recognised, Campylobacter jejuni remains the most relevant pathogen. The main infection source is raw chicken, but cases including cattle and domestic animals, such as cats, have been reported recently [2]. Infection with Campylobacter can cause diarrhoea and can be critical for patients of higher risk, such as elderly people, and immunocompromised patients. In these critical cases, the gold standard treatment is the administration of antibiotics. However, antibiotic susceptibility is challenged by the emergence of antibiotic resistance [3]. Tracking the source of an infection as well as understanding the spread of the organism in animal production systems are important steps in reducing the impact of this organism and require effective, efficient typing methods

The current gold standard method for typing is multi-locus sequence typing (MLST). MLST, however, is not applicable to the standard laboratory due to the lack of cost efficiency and time consumption [4]. Therefore, we performed Campylobacter jejuni genotyping by allele-specific multiplex–microsphere quantitative PCR detection within 4 hours [1]. A high resolution of genotypes is possible as the single-nucleotide polymorphisms (SNP) within the MLST genes targeted are selected on the basis of highest possible Simpson´s index of diversity (D). This new approach is currently being extended to include presence/absence assays (e.g. antibiotic resistance and virulence genes) to improve the power of the typing. In other applications, we are exploring direct detection and typing of pathogens in other complex diseases, such as sepsis.