Globetrotting strangles: the unbridled national and international transmission of Streptococcus equi between horses.
Abstract: The equine disease strangles, which is characterized by the formation of abscesses in the lymph nodes of the head and neck, is one of the most frequently diagnosed infectious diseases of horses around the world. The causal agent, subspecies , establishes a persistent infection in approximately 10 % of animals that recover from the acute disease. Such 'carrier' animals appear healthy and are rarely identified during routine veterinary examinations pre-purchase or transit, but can transmit to naïve animals initiating new episodes of disease. Here, we report the analysis and visualization of phylogenomic and epidemiological data for 670 isolates of recovered from 19 different countries using a new core-genome multilocus sequence typing (cgMLST) web bioresource. Genetic relationships among all 670 S. isolates were determined at high resolution, revealing national and international transmission events that drive this endemic disease in horse populations throughout the world. Our data argue for the recognition of the international importance of strangles by the Office International des Épizooties to highlight the health, welfare and economic cost of this disease. The Pathogenwatch cgMLST web bioresource described herein is available for tailored genomic analysis of populations of and its close relative subspecies that are recovered from horses and other animals, including humans, throughout the world. This article contains data hosted by Microreact.
Publication Date: 2021-03-08 PubMed ID: 33684029PubMed Central: PMC8190609DOI: 10.1099/mgen.0.000528Google Scholar: Lookup
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Summary
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The article explores how the equine disease known as strangles, caused by the Streptococcus equi bacterium, is transmitted between horses both domestically and internationally. Using genomic and epidemiological data from various countries, the authors argue for international recognition of the disease’s impact on health, welfare, and economic cost.
Introduction to Strangles and Streptococcus equi
- Strangles is an infectious disease that affects horses and is one of the most frequently diagnosed worldwide. The disease results in the formation of abscesses in the lymph nodes of horses’ heads and necks.
- The bacterium Streptococcus equi is the causative agent of strangles. Notably, it establishes persistent infections in about 10% of animals that recover from the acute disease.
- Carriers of the bacterium appear healthy and don’t usually get identified, which allows for the unchecked spread of the disease because these carriers can transmit the bacterium to other horses.
Epidemiological Analysis of Streptococcus equi
- The researchers used a new core-genome multilocus sequence typing (cgMLST) web bioresource to analyze and visualize phylogenomic and epidemiological data for 670 isolates of Streptococcus equi.
- The isolates were gathered from 19 different countries, enabling the researchers to map out the global transmission events.
- The high-resolution analysis allowed the researchers to determine genetic relationships among all 670 isolates, which revealed patterns of both domestic and international transmission of the disease.
Arguing for International Recognition and The Pathogenwatch Web Bioresource
- The data acquired clearly demonstrate the international importance of strangles, influencing the health and welfare of horses, and also having an economic impact.
- This research argues for the recognition of strangles by the Office International des Épizooties, a reference organization for animal diseases.
- The authors also describe the Pathogenwatch cgMLST web bioresource that is available for customized genomic analysis of populations of Streptococcus equi.
- This resource can also be used to investigate the bacterium’s close relative, Streptococcus equi subspecies, which can infect not just horses, but other animals, including humans.
Cite This Article
APA
Mitchell C, Steward KF, Charbonneau ARL, Walsh S, Wilson H, Timoney JF, Wernery U, Joseph M, Craig D, van Maanen K, Hoogkamer-van Gennep A, Leon A, Witkowski L, Rzewuska M, Stefańska I, Żychska M, van Loon G, Cursons R, Patty O, Acke E, Gilkerson JR, El-Hage C, Allen J, Bannai H, Kinoshita Y, Niwa H, Becú T, Pringle J, Guss B, Böse R, Abbott Y, Katz L, Leggett B, Buckley TC, Blum SE, Cruz López F, Fernández Ros A, Marotti Campi MC, Preziuso S, Robinson C, Newton JR, Schofield E, Brooke B, Boursnell M, de Brauwere N, Kirton R, Barton CK, Abudahab K, Taylor B, Yeats CA, Goater R, Aanensen DM, Harris SR, Parkhill J, Holden MTG, Waller AS.
(2021).
Globetrotting strangles: the unbridled national and international transmission of Streptococcus equi between horses.
Microb Genom, 7(3), mgen000528.
https://doi.org/10.1099/mgen.0.000528 Publication
Researcher Affiliations
- Animal Health Trust, Newmarket, UK.
- Animal Health Trust, Newmarket, UK.
- Present address: Technology Networks, Sudbury, UK.
- Present address: Xampla, Cambridge, UK.
- Animal Health Trust, Newmarket, UK.
- Present address: University of Berlin, Berlin, Germany.
- Animal Health Trust, Newmarket, UK.
- Present address: University of Cambridge, Cambridge, UK.
- Animal Health Trust, Newmarket, UK.
- Gluck Equine Research Center, Lexington, USA.
- Central Veterinary Research Laboratory, Dubai, UAE.
- Central Veterinary Research Laboratory, Dubai, UAE.
- Emirates Racing Authority, Dubai, UAE.
- Animal Health Service (GD), Deventer, The Netherlands.
- Animal Health Service (GD), Deventer, The Netherlands.
- Labéo Frank Duncombe, Caen, France.
- Institute of Veterinary Medicine, Warsaw University of Life Sciences - SGGW, Warsaw, Poland.
- Institute of Veterinary Medicine, Warsaw University of Life Sciences - SGGW, Warsaw, Poland.
- Institute of Veterinary Medicine, Warsaw University of Life Sciences - SGGW, Warsaw, Poland.
- Institute of Veterinary Medicine, Warsaw University of Life Sciences - SGGW, Warsaw, Poland.
- Ghent University, Merelbeke, Belgium.
- University of Waikato, Hamilton, New Zealand.
- University of Waikato, Hamilton, New Zealand.
- Massey University, Palmerston North, New Zealand.
- University of Melbourne, Melbourne, Australia.
- University of Melbourne, Melbourne, Australia.
- University of Melbourne, Melbourne, Australia.
- Japan Racing Association, Tochigi, Japan.
- Japan Racing Association, Tochigi, Japan.
- Japan Racing Association, Tochigi, Japan.
- Clinica Equina, Buenos Aires, Argentina.
- Department of Biomedical Science and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden.
- Department of Biomedical Science and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden.
- Labor Dr Böse GmbH, Harsum, Germany.
- University College Dublin, Dublin, Ireland.
- University College Dublin, Dublin, Ireland.
- University College Dublin, Dublin, Ireland.
- Irish Equine Centre, Naas, Ireland.
- Kimron Veterinary Institute, Bet Dagan, Israel.
- Universidad Complutense, Madrid, Spain.
- Exopol, Zaragoza, Spain.
- Al Khalediah Equine Hospital, Riyadh, Saudi Arabia.
- University of Camerino, Camerino, Italy.
- Animal Health Trust, Newmarket, UK.
- Animal Health Trust, Newmarket, UK.
- Present address: University of Cambridge, Cambridge, UK.
- Animal Health Trust, Newmarket, UK.
- Animal Health Trust, Newmarket, UK.
- Animal Health Trust, Newmarket, UK.
- Redwings Horse Sanctuary, Norwich, UK.
- Present address: Royal Society for the Prevention of Cruelty to Animals, Horsham, UK.
- Redwings Horse Sanctuary, Norwich, UK.
- Weatherford Equine Medical Centre, Weatherford, TX, USA.
- Centre for Genomic Pathogen Surveillance, Wellcome Trust Sanger Institute, Cambridge, UK.
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Centre for Genomic Pathogen Surveillance, Wellcome Trust Sanger Institute, Cambridge, UK.
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Centre for Genomic Pathogen Surveillance, Wellcome Trust Sanger Institute, Cambridge, UK.
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Centre for Genomic Pathogen Surveillance, Wellcome Trust Sanger Institute, Cambridge, UK.
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Centre for Genomic Pathogen Surveillance, Wellcome Trust Sanger Institute, Cambridge, UK.
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Present address: Microbiotica Limited, Cambridge, UK.
- Centre for Genomic Pathogen Surveillance, Wellcome Trust Sanger Institute, Cambridge, UK.
- University of Cambridge, Cambridge, UK.
- University of St Andrews, St Andrews, UK.
- Centre for Genomic Pathogen Surveillance, Wellcome Trust Sanger Institute, Cambridge, UK.
- Intervacc AB, Stockholm, Sweden.
- Animal Health Trust, Newmarket, UK.
- Department of Biomedical Science and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden.
MeSH Terms
- Animals
- Female
- Genome, Bacterial
- Horse Diseases / microbiology
- Horse Diseases / transmission
- Horses
- Male
- Phylogeny
- Streptococcal Infections / microbiology
- Streptococcal Infections / transmission
- Streptococcal Infections / veterinary
- Streptococcus equi / classification
- Streptococcus equi / genetics
- Streptococcus equi / isolation & purification
- Streptococcus equi / physiology
Grant Funding
- Wellcome Trust
- 098051 / Wellcome Trust
- 098051 / Wellcome Trust
Conflict of Interest Statement
A.S.W. is employed by Intervacc AB.
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