Characterization of virulence profiles and antimicrobial resistance patterns of clinical and environmental Vibrio parahaemolyticus isolated in Canada
department or school: Land and Food Systems, Faculty of
data provider: DSpace
degree campus: UBCV
creator: Liu, Jennifer
issued: 2017-04-18T18:31:13Z
issued: 2017
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Vibrio parahaemolyticus is a naturally occurring marine organism with a worldwide distribution in estuaries and coastal environments. Consequently, V. parahaemolyticus bio-accumulates in the gut of filter-feeding molluscan shellfish (e.g. oysters) and is a common cause of seafood associated gastroenteritis. Recent data show increased rates of V. parahaemolyticus infection in Canada, particularly British Columbia (BCCDC, 2015; PHAC, 2014). To further improve our understanding of the types of V. parahaemolyticus strains that exist in the Canadian (primarily British Columbia) environment and facilitate assessment of risk to public health, virulence profiles and antimicrobial resistance (AMR) patterns were determined for 600 isolates collected between 1998 and 2011. Clinical isolates (n=64) and environmental strains (n=536) cultured from oysters collected from Canadian growing areas were analyzed in this study. A multiplex PCR assay was used to confirm all isolates as V. parahaemolyticus and characterize virulence gene profiles (tdh and trh). AMR phenotypes were determined by a disc diffusion assay using a panel of 20 clinically relevant antibiotics. Further sub-typing using multi-locus sequence typing (MLST) was conducted on a subset (clinical, n=31; environmental, n=135) of isolates. Results showed 53% of clinical and 8% of environmental isolates possess at least one of the virulence markers. Overall levels of AMR were low, with 7% of isolates exhibiting pansusceptibility and 0.5% displaying resistance to 4 antibiotics. Ampicillin resistance was widespread (91%) with resistance to cephalothin (29%), streptomycin (4.3%), sulfisoxazole (2.7%), piperacillin (2.3%), oxolinic acid (0.5%), ceftiofur (0.4%), gentamicin (0.2%), and kanamycin (0.2%) also seen. MLST analysis showed the V. parahaemolyticus population structure is genetically diverse with 36 novel sequence types (STs) identified, all recovered from environmental isolates. In comparison, a smaller number of STs ap…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/61245
note: Characterization of Virulence Profiles and Antimicrobial Resistance Patterns of Clinical and Environmental Vibrio parahaemolyticus Isolated in Canada by Jennifer Liu BSc., Simon Fraser University, 2000 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Food Science) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) April 2017 © Jennifer Liu, 2017 ii Abstract Vibrio parahaemolyticus is a naturally occurring marine organism with a worldwide distribution in estuaries and coastal environments. Consequently, V. parahaemolyticus bio-accumulates in the gut of filter-feeding molluscan shellfish (e.g. oysters) and is a common cause of seafood associated gastroenteritis. Recent data show increased rates of V. parahaemolyticus infection in Canada, particularly British Columbia (BCCDC, 2015; PHAC, 2014). To further improve our understanding of the types of V. parahaemolyticus strains that exist in the Canadian (primarily British Columbia) environment and facilitate assessment of risk to public health, virulence profiles and antimicrobial resistance (AMR) patterns were determined for 600 isolates collected between 1998 and 2011. Clinical isolates (n=64) and environmental strains (n=536) cultured from oysters collected from Canadian growing areas were analyzed in this study. A multiplex PCR assay was used to confirm all isolates as V. parahaemolyticus and characterize virulence gene profiles (tdh and trh). AMR phenotypes were determined by a disc diffusion assay using a panel of 20 clinically relevant antibiotics. Further sub-typing using multi-locus sequence typing (MLST) was conducted on a subset (clinical, n=31; environmental, n=135) of isolates. Results showed 53% of clinical and 8% of environmental isolates possess at least one of the virulence markers. Overall levels of AMR were low, with 7% of isolates exhibiting pansusceptibility and 0.5% displaying resistance to 4 antibiotics…
has type: Thesis/Dissertation
date issued: 2017-05
is shown at: 10.14288/1.0343648
language: eng
degree discipline: Food Science
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/61245