title: Outbreak of cholera caused by Vibrio cholerae O1 El Tor variant strain in Bihar, India.
abstract: An outbreak of cholera struck Bihar, an Indian state, in August 2008 following a massive flood. Here we report the phenotypic and genotypic characteristics of Vibrio cholerae strains isolated from patients with diarrhea. Rectal swabs were obtained from patients with diarrhea who were admitted to medical camps or the hospital, and the strains were biochemically and serologically characterized. V. cholerae was isolated from 21 (65.6%) of 32 rectal swabs. Serological studies revealed that all the 21 isolates belonged to V. cholerae O1 Ogawa. Mismatch amplification mutation assay (MAMA)-PCR showed that the isolates belonged to El Tor variant group, and pulsed-field gel electrophoresis (PFGE) proved that these isolates were of a different lineage than the conventional El Tor variant strains. These isolates were resistant to several drugs, including ampicillin, streptomycin, tetracycline, nalidixic acid, and furazolidone. The uniqueness of the current report arises from the fact that records of cholera in Bihar are availiable for the early 1960s but not for the next 4 decades. Moreover, the present study is the first to report a cholera outbreak in Bihar that was caused by an El Tor variant strain.
authors.affiliation: Division of Bacteriology, National Institute of Cholera and Enteric Diseases.
authors.forename: Hemanta
authors.initials: H
authors.lastname: Koley
authors.forename: Nivedita
authors.initials: N
authors.lastname: Ray
authors.forename: Goutam
authors.initials: G
authors.lastname: Chowdhury
authors.forename: Soumik
authors.initials: S
authors.lastname: Barman
authors.forename: Soma
authors.initials: S
authors.lastname: Mitra
authors.forename: T
authors.initials: T
authors.lastname: Ramamurthy
authors.forename: Asish K
authors.initials: AK
authors.lastname: Mukhopadhyay
authors.forename: B L
authors.initials: BL
authors.lastname: Sarkar
authors.forename: Rakesh
authors.initials: R
authors.lastname: Katyal
authors.forename: Pradeep
authors.initials: P
authors.lastname: Das
authors.forename: Samiran
authors.initials: S
authors.lastname: Panda
authors.forename: Subrata
authors.initials: S
authors.lastname: Ghosh
mesh_terms: D002771:Cholera / Q000453:epidemiology* / Q000382:microbiology*; D003967:Diarrhea / Q000382:microbiology; D004190:Disasters; D004196:Disease Outbreaks / Q000706:statistics & numerical data*; D055868:Floods; D006801:Humans; D007194:India / Q000453:epidemiology; D010641:Phenotype; D012007:Rectum / Q000382:microbiology; D041241:Vibrio cholerae O1 / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*