Dr Sheu BS and Dr Wu JJ coordinated the conduct of the whole st

Dr. Sheu BS and Dr. Wu JJ coordinated the conduct of the whole study and made interpretation of data. Chiang WC, Kao CY and Wu HM conducted the acquisition of data. Dr. Yang HB reviewed the pathology. All authors read and approved the final manuscript.”
“Background Diarrhoeal diseases have been and continue to be a cause of mortality and morbidity, especially in developing countries. Of particular note is the disease cholera, a severe watery diarrhoeal disease caused by Vibrio cholerae. V. cholerae is a diverse species of Gram negative bacilli. Serological testing has enabled

strains of V. cholerae to be divided into over Selleck BGB324 200 serogroups based on the O-antigen present [1]. However, only the O1 and O139 serogroups have been known to cause pandemic and epidemic level disease [2]. Since 1817, seven pandemics of cholera have been recorded [3]. The ongoing epidemic started in 1961 and has affected almost every continent,

particularly countries of Southeast Asia, Africa, and South America. Cholera remains endemic in developing countries and outbreaks still pose a significant public health issue [4]. The developments of DNA based typing methods have allowed epidemiological studies of cholera. Methods such as Pulse Field Gel Electrophoresis [5, 6], Amplified Fragment Length Polymorphism [7] as well as population structure studies including Multi-Locus Sequence Typing [8–10] have all been applied to V. cholerae isolates. Such methods have all been able to distinguish www.selleckchem.com/products/chir-98014.html between environmental and clinical strains of V. cholerae[6, 8, 11], but they have had limited success in drawing evolutionary relationships between 7th pandemic strains. Previously, we

investigated the evolution of V. cholerae using oxyclozanide Single Nucleotide Polymorphism (SNP) analysis and found that 7th pandemic V. cholerae isolates could be distinguished into groups with a stepwise accumulation of SNPs. The 7th pandemic SNP relationships were confirmed by a large genome sequencing based study by Mutreja et al. [12]. SNP Groups were correlated with the spread of pandemic cholera into Africa and were also able to separate the O139 isolates into a distinct SNP profile [13]. However, further resolution of isolates within each group is required. Multilocus variable number tandem https://www.selleckchem.com/EGFR(HER).html repeat analysis (MLVA) is a PCR based typing method based on regions of tandemly repeated short DNA sequence elements. Variations in the number of copies of repeat DNA sequences form the basis of differentiation [14]. Recent studies have shown that MLVA is a highly discriminating method for the typing of environmental and clinical isolates of V. cholerae and is able to differentiate closely related isolates from outbreak situations [15, 16]. In this report, we applied MLVA to isolates spanning the 7th pandemic to further determine the genetic and evolutionary relationships within the 7th pandemic clone and to evaluate the potential of MLVA as a long term epidemiological typing tool.

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