title: Biotype traits and antibiotic susceptibility of Vibrio cholerae serogroup O1 before, during and after the emergence of the O139 serogroup.
abstract: Sixty-nine strains of Vibrio cholerae O1 isolated at different times were analysed to investigate if there were any differences among the O1 strains isolated before, during and after the advent of the O139 serogroup. Of the 69 O1 strains examined, 68 belonged to the Ogawa serotype while one belonged to the Inaba serotype. With the exception of one strain all other strains of V. cholerae O1 belonged to the eltor biotype. A single O1 strain isolated before the emergence of the O139 serogroup could not be classified as either eltor or classical biotype because it was resistant to both classical and eltor specific bacteriophages. Marked variations in the susceptibility to antibiotics of V. cholerae O1 isolated during the different periods were observed. In addition, strains of V. cholerae isolated after the epidemic of serogroup O139 in Calcutta showed an expanding R-type with resistance to a variety of drugs as compared to the O1 strains isolated before the advent of the O139 serogroup. From this study, it is clear that there is a substantial mobility in genetic elements of V. cholerae O1 which necessitates a continuous monitoring to keep abreast of the changing traits of the etiologic agent of cholera.
authors.affiliation: Department of Microbiology, National Institute of Cholera and Enteric Diseases, Beliaghata, Calcutta, India.
authors.forename: A K
authors.initials: AK
authors.lastname: Mukhopadhyay
authors.forename: S
authors.initials: S
authors.lastname: Garg
authors.forename: G B
authors.initials: GB
authors.lastname: Nair
authors.forename: S
authors.initials: S
authors.lastname: Kar
authors.forename: R K
authors.initials: RK
authors.lastname: Ghosh
authors.forename: S
authors.initials: S
authors.lastname: Pajni
authors.forename: A
authors.initials: A
authors.lastname: Ghosh
authors.forename: T
authors.initials: T
authors.lastname: Shimada
authors.forename: T
authors.initials: T
authors.lastname: Takeda
authors.forename: Y
authors.initials: Y
authors.lastname: Takeda
mesh_terms: D000372:Agglutination Tests; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015373:Bacterial Typing Techniques; D002771:Cholera / Q000453:epidemiology / Q000382:microbiology*; D002772:Cholera Toxin / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis; D003967:Diarrhea / Q000382:microbiology; D004352:Drug Resistance, Microbial; D005243:Feces / Q000382:microbiology; D005798:Genes, Bacterial; D006801:Humans; D015994:Incidence; D007194:India / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D012703:Serotyping; D014734:Vibrio cholerae / Q000145:classification* / Q000187:drug effects / Q000302:isolation & purification / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D002772:Cholera Toxin