Vibrioand Related Organisms

Abstract

This chapter focuses on the various Vibrionaceae species that cause disease in humans. Vibrio is the type genus for the family, and Vibrio cholerae, the causative agent of pandemic cholera, is the type species. The genera covered in the chapter are primarily isolated from marine environments. Recent studies have shown that in mixed populations of nonculturable and culturable cells of V. cholerae, the latter appear to be the main contributors to human infections. The majority of persons ingesting toxigenic V. cholerae O1 have asymptomatic infections. Most of the advantages of PCR-based assays over culture methods apply to vibrios and include the ability to freeze stools for epidemiological studies for delayed testing. Molecular identification of vibrios is commonplace in surveys and in research studies. However, it is not commonly employed in clinical laboratories for routine identification because vibrios are relatively rare pathogens in noncoastal areas or regions where cholera is not endemic. The clinical significance of Vibrio strains in other specimens, particularly stool, may be more difficult to determine and requires prompt consultation with the attending physician to better understand the clinical context. Vibrionaceae isolates should also be submitted to public health laboratories, as they are monitored under the CDC’s International Emerging Infections Program and Vibrio Surveillance System; they may also be needed for confirmation and toxin testing. Misidentification of Vibrio species and their relatives can be a problem in the literature unless investigators used methods that are very sensitive in differentiating all of the species in the family Vibrionaceae.