Same-Day Subtyping of Campylobacter jejuni and C. coli Isolates by Use of Multiplex Ligation-Dependent Probe Amplification–Binary Typing

Campylobacteriosis is the most commonly reported form of human bacterial gastroenteritis in the world. Sound identification of infectious sources requires subtyping, but the most widely used methods have turnaround times measured in days and re-quire specialist equipment and skills. A multiplex ligation-dependent probe amplification-binary typing (MBiT) assay was devel-oped for subtyping Campylobacter jejuni and Campylobacter coli. It was tested on 245 isolates, including recent isolates from Belgium and New Zealand, and compared to multilocus sequence typing (MLST). When used in an outbreak setting, MBiT iden-tified the predominant genotype and possible additional cases days before pulsed-field gel electrophoresis (PFGE) results were available. MBiT was more discriminatory thanMLST and, being a single assay with results produced within 6 h, was more rapid and cost-effective than bothMLST and PFGE. In addition, MBiT requires only basic molecular biology equipment and skills. Campylobacter species, notably Campylobacter jejuni and Cam-pylobacter coli, are the most commonly reported bacterial causes of human gastroenteritis in the world (1). They are widely distributed in nature (2), and ingestion of contaminated food or water is a major route of human infection (3). Identification of sources and infectious trends is often vital for informing control measures, and this process requires subtyping of isolates. A variety of subtyping methods are available for Campylobacter, with th