Abstract
Only about half the cases of intestinal infectious disease have a routinely detectable causative agent diagnosed. Increasingly, evidence indicates that Campylobacter species other than C. jejuni and C. coli are associated with such cases. However, evidence is less clear, from epidemiological studies, for the pathogenic nature of these unusual campylobacters. This is particularly true for organisms like C. concisus and is compounded by poor methods for routine recovery and identification. Moreover, the application of typing methods for C. concisus has indicated a heterogeneous population and there is preliminary evidence to suggest differences in the pathogenic potential of strain types. However, considerable further work is needed with more discriminatory genotyping methods, before accurate assessment of the risk of C. concisus infection to human health can be determined.