Research
Title : | Study of interepidemic survival of V. cholerae in outbreak prone areas of Assam |
Area of research : | Medical Sciences |
Focus area : | Cholera and enteric diseases |
Principal Investigator : | Dr. Jagadish Mahanta, Scientist, Regional Medical Research Centre (RMRC), Assam |
Timeline Start Year : | 2014 |
Timeline End Year : | 2016 |
Contact info : | jmahanta@gmail.com; bborkakoty.rmrcne@gov.in |
Details
Executive Summary : | It is observed that there were no reports of cholera outbreak in this part of Assam. While from January 2016 V. cholerae began to be positive in environmental samples in non culturable form by PCR and gradually positivity increased in more samples collected from different sites from february 2016 and percent positivity of the samples were highest from April 2016 to June 2016 which coincided with the outbreak in Manjushree tea garden of Sivasagar district. In the interepidemic period no V. cholerae was isolated nor detected by PCR in the rectal swabs collected from the study sites. Although V. cholerae O1 could not be detected by PCR nor could be recovered in culture it is observed that nonO1 and nonO139 was predominant in the water samples collected from the study sites which were non culturable and were detected by presence of OmpW gene specific for V.cholerae and negative for O1rfb and o139rfb genes by PCR. The genetic profile in few of the NonO1 and non O139 V. cholerae resembled with the epidemic strain of Manjushree tea garden of Sibsagar District except for the CtxA and CtxB genes. Towards approaching nearer to warmer months the percent positivity of the water samples increased indicating environmental conditions conducive for growth of V. cholerae following which the concentration of the cells increased gradually and reverted back from VBNC state which might have led to an outbreak. It is also evident from the study that there is existence of an environmental reservoir of pathogenic genes among nonO1 and non O139 V.cholerae which makes an opportunity for an emergence of pathogenic epidemic strain of V. cholerae in this region. Also there might be a possibility that conversion of serogroup might have occured within the non V.cholerae strain. |
Co-PI: | Dr. Pranjal Jyoti Baruah, Scientist, Regional Medical Research Centre (RMRC), Assam, Dr. Utpala Devi, Scientist, Regional Medical Research Centre (RMRC), Assam, Dr. B.J Borkakoty, Scientist, Regional Medical Research Centre (RMRC), Assam, Dr. P.K.Mohapatra, Scientist, Regional Medical Research Centre (RMRC), Assam |
Organizations involved
Implementing Agency : | Regional Medical Research Centre (RMRC), Dibrugarh, Assam 786001 Funding Agency :Indian Council of Medical Research (ICMR), New Delhi | |