Epidemiology and Infection

Original Papers


Large outbreak of cholera caused by El Tor variant Vibrio cholerae O1 in the eastern coast of Odisha, India during 2009

B. B. PALa1, H. K. KHUNTIAa1 c1, S. K. SAMALa1, A. S. KERKETTAa1, S. K. KARa1, M. KARMAKARa2 and B. PATTNAIKa3

a1 Microbiology Division, Regional Medical Research Centre, ICMR, Odisha, India

a2 National Rural Health Mission, Bhubaneswar, Odisha, India

a3 Integrated Disease Surveillance Project, Directorate of Health Services, Government of Odisha, India


A large outbreak of cholera reported during April–July 2009 in the Kendrapada district of Odisha, India was investigated. Forty-one rectal swabs and 41 water samples, collected from diarrhoeal patients and from different villages were bacteriologically analysed for the isolation of bacterial enteriopathogens, antibiogram profile and detection of various toxic genes. The bacteriological analysis of rectal swabs and environmental water samples revealed the presence of V. cholerae O1 Ogawa biotype El Tor. The V. cholerae strains were resistant to ciprofloxacin, co-trimoxazole, chloramphenicol, streptomycin, ampicillin, furazolidone and nalidixic acid. The multiplex polymerase chain reaction (PCR) assay on V. cholerae strains revealed the presence of ctxA and tcpA genes. The mismatch amplification of mutation assay (MAMA) PCR on clinical and environmental isolates of V. cholerae revealed that the strains were El Tor biotype, which harboured the ctxB gene of the classical strain. The random amplified polymorphic DNA PCR analysis and pulsed-field gel electrophoresis results indicated that the V. cholerae isolates belonged to the same clone. This investigation gives a warning that the El Tor variant of V. cholerae has spread to the coastal district causing a large outbreak that requires close monitoring and surveillance on diarrhoeal outbreaks in Odisha.

(Received July 28 2012)

(Revised August 24 2012)

(Accepted January 30 2013)

(Online publication March 06 2013)

Key words

  • El Tor variant Vibrio cholerae ;
  • Odisha;
  • spread


c1 Author for correspondence: Dr H. K. Khuntia, Microbiology Division, Regional Medical research Centre (ICMR), Bhubaneswar 751023, Odisha, India. (Email: khuntia_hk@yahoo.co.in)