Professor CHUN Jongsik of SNU's Department of Biological Sciences and KIM Dong Wook, Ph.D of the International Vaccine Institute, through the use of next-generation whole-genome identification methods, have succeeded in identifying the origin and expansion path of the current cholera pandemic.

This research was conducted in joint collaboration with the Wellcome Trust Sanger Institute in the United Kingdom, and was published in the August 25 online edition of Nature.

According to their research results, the specific cholera pandemic that spread after the Haitian earthquake in October 2010 originated from an ancestor strain that appeared from the Bay of Bengal approximately 40 years ago.

The research team analyzed the genome sequence of the causative bacterium 'Vibrio cholerae,' taken from 154 cases reported worldwide in the last 40 years, to track down the spread of the pathogen. Upon analysis of singular DNA transitions inside the genome sequence of the V. cholerae, the team was able to trace its expansion path on a world map.

The current cholera pandemic, which first appeared in the 1950s and is still ongoing, originated from the Bay of Bengal and spread to other continents over at least three outbreaks with three different ancestor strains.

The research team related such movement of cholera with the traveling activities of humans across the world.

Dr. Kim of the International Vaccine Institute explained that"This study was one of the first to conduct comprehensive analysis on the variants of the V. cholerae pathogen and genomic data in order to follow the movement and evolution of cholera over several different continents."

The results of this research are expected to be put to use in the establishment of future public health plans and further research in back-tracking the first outbreak of cholera. It will also help in understanding the expansion mechanism of cholera, with which three to five million people are infected every year, causing over 100,000 deaths.

Dr. Julian Parkhill of the Wellcome Trust Sanger Institute, a co-author of the consequent research paper, claimed that"This goes against previous beliefs that cholera always arises from local strains, and provides useful information in understanding cholera outbreaks."

G. Balakrish Nair, director of the National Institute of Cholera and Enteric Diseases in India, also recognized the significance of the research, saying that"These findings in due course will lead us to understand why cholera pandemics begin in Southeast Asia and then spread as a wave across the world."

Cecil Czerkinsky, deputy director-general for laboratory sciences at the International Vaccine Institute, emphasized that this research and its discoveries will"present a new approach for researchers in tracking down the movement forms and finding the origins of contagious diseases."

Written by KIM Eun Young, SNU English Editor, bittersweet@snu.ac.kr ?
Proofread by Brett Johnson, SNU English Editor, morningcalm2@gmail.com