title: A rapid and reliable species-specific identification of clinical and environmental isolates of Vibrio cholerae using a three-test procedure and recA polymerase chain reaction.
abstract: OBJECTIVE
  Vibrio cholerae, the cause of cholera, is one of the leading causes of morbidity and mortality in many developing countries. Most laboratories initially rely on biochemical tests for a presumptive identification of these strains, followed by a polymerase chain reaction (PCR)-based method to confirm their identification. The aim of this study is to establish a rapid and reliable identification scheme for V. cholerae using a minimal, but highly specific number of biochemical tests and a PCR assay.
  
  
  METHODS
  We developed a species-specific PCR to identify V. cholerae, using a housekeeping gene recA, and used that to evaluate the sensitivity and specificity of 12 biochemical tests commonly used for screening and / or presumptive identification of V. cholerae in the clinical and environmental samples.
  
  
  RESULTS
  Here we introduced a combination of three biochemical tests, namely, sucrose fermentation, oxidase test, and growth in trypton broth containing 0% NaCl, as also the PCR of the recA gene, for rapid identification of V. cholerae isolates, with 100% sensitivity and specificity. The established method accurately identified a collection of 47 V. cholerae strains isolated from the clinical cases (n = 26) and surface waters (n = 21), while none of the 32 control strains belonging to different species were positive in this assay.
  
  
  CONCLUSIONS
  The triple-test procedure introduced here is a simple and useful assay which can be adopted in cholera surveillance programs for efficient monitoring of V. cholerae in surface water and fecal samples.
authors.affiliation: Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: A D
authors.initials: AD
authors.lastname: Roozbehani
authors.forename: B
authors.initials: B
authors.lastname: Bakhshi
authors.forename: M R
authors.initials: MR
authors.lastname: Pourshafie
authors.forename: M
authors.initials: M
authors.lastname: Katouli
mesh_terms: D015373:Bacterial Typing Techniques / Q000379:methods*; D004783:Environmental Microbiology; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*; D011938:Rec A Recombinases / Q000235:genetics; D012680:Sensitivity and Specificity; D014734:Vibrio cholerae / Q000145:classification* / Q000302:isolation & purification* / Q000472:pathogenicity
chemical_list: D011938:Rec A Recombinases