The Lake Chad Basin, an Isolated and Persistent Reservoir of Vibrio cholerae O1: A Genomic Insight into the Outbreak in Cameroon, 2010

Rolf S Kaas; Antoinette Ngandjio; Ariane Nzouankeu; Achiraya Siriphap; Marie-Christine Fonkoua; Frank M Aarestrup; Rene S Hendriksen

doi:10.1371/journal.pone.0155691

The Lake Chad Basin, an Isolated and Persistent Reservoir of Vibrio cholerae O1: A Genomic Insight into the Outbreak in Cameroon, 2010

PLoS One. 2016 May 18;11(5):e0155691. doi: 10.1371/journal.pone.0155691. eCollection 2016.

Authors

Rolf S Kaas¹, Antoinette Ngandjio², Ariane Nzouankeu³, Achiraya Siriphap^{4

5}, Marie-Christine Fonkoua³, Frank M Aarestrup¹, Rene S Hendriksen¹

Affiliations

¹ National Food Institute, Technical University of Denmark, Research Group for Genomic Epidemiology, WHO Collaborating Center for Antimicrobial Resistance in Foodborne Pathogens and European Union Reference Laboratory for Antimicrobial Resistance, Kgs. Lyngby, Denmark.
² Centre Pasteur du Cameroon, Service Hygiène et Environnement section Microbiologie, P.O. Box 1274, Yaoundé, Cameroon.
³ Centre Pasteur du Cameroon, Laboratory of Bacteriology, P.O. Box 1274, Yaoundé, Cameroon.
⁴ Department of Microbiology and Parasitology, Faculty of Medical Science, University of Phayao, Phayao, 56000, Thailand.
⁵ Department of Microbiology, Faculty of Public Health, Mahidol University, Bangkok, 10400, Thailand.

Abstract

The prevalence of reported cholera was relatively low around the Lake Chad basin until 1991. Since then, cholera outbreaks have been reported every couple of years. The objective of this study was to investigate the 2010/2011 Vibrio cholerae outbreak in Cameroon to gain insight into the genomic make-up of the V. cholerae strains responsible for the outbreak. Twenty-four strains were isolated and whole genome sequenced. Known virulence genes, resistance genes and integrating conjugative element (ICE) elements were identified and annotated. A global phylogeny (378 genomes) was inferred using a single nucleotide polymorphism (SNP) analysis. The Cameroon outbreak was found to be clonal and clustered distant from the other African strains. In addition, a subset of the strains contained a deletion that was found in the ICE element causing less resistance. These results suggest that V. cholerae is endemic in the Lake Chad basin and different from other African strains.

Publication types

Historical Article
Research Support, Non-U.S. Gov't

MeSH terms

Anti-Bacterial Agents / pharmacology
Cameroon / epidemiology
Cholera / epidemiology*
Cholera / history
Cholera / microbiology*
Disease Outbreaks*
Disease Reservoirs*
Genome, Bacterial
Genotype
History, 21st Century
Humans
Lakes / microbiology*
Microbial Sensitivity Tests
Multilocus Sequence Typing
Phylogeny
Polymorphism, Single Nucleotide
Sequence Analysis, DNA
Serogroup
Vibrio cholerae O1 / classification
Vibrio cholerae O1 / drug effects
Vibrio cholerae O1 / genetics*
Vibrio cholerae O1 / isolation & purification

Substances

Anti-Bacterial Agents

Grants and funding

This work was supported by the Danish Council for Strategic Research (grant number: 09-067103), Center for Genomic Epidemiology (www.genomicepidemiology.org), and by the World Health Organization Global Foodborne Infections Network (www.who.int/gfn). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.