Campylobacter in fresh retail meat: species diversity assessment using a modified filter method compared with ISO...

A modified filter method was developed to improve the recovery of diverse Campylobacter species from fresh meat. Its performance was evaluated using strains from 10 Campylobacter species considered relevant to human health, and the protocol was subsequently applied to 289 fresh meat samples (129 pork, 80 chicken, 80 beef) collected from butcheries and supermarkets in Flanders, Belgium. The modified filter method successfully recovered five known Campylobacter species-C. jejuni, C. coli, C. concisus, C. lari, and C. mucosalis-as well as two potentially novel Campylobacter spp. This approach yielded a greater species diversity compared to ISO 10272, which was applied in parallel to a subset of 234 samples and recovered only three species. All isolates were accurately identified using MALDI-TOF MS and whole-genome sequencing. Neither method isolated C. jejuni nor C. coli from pork or beef. Remarkably, the clinically relevant C. concisus was isolated from pork in high numbers (14%). Furthermore, a previously reported PCR-based species identification method was evaluated. It lacked sufficient specificity, particularly for C. concisus, thereby introducing identification bias on top of the already underreported presence of uncommon Campylobacter species.