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Research article - Peer-reviewed, 2021

Globetrotting strangles: the unbridled national and international transmission of Streptococcus equi between horses

Mitchell, Catriona; Steward, Karen F.; Charbonneau, Amelia R. L.; Walsh, Saoirse; Wilson, Hayley; Timoney, John F.; Wernery, Ulli; Joseph, Marina; Craig, David; van Maanen, Kees; Hoogkamer- van Gennep, Annelies; Leon, Albertine; Witkowski, Lucjan; Rzewuska, Magdalena; Stefanska, Ilona; Zychska, Monika; van Loon, Gunther; Cursons, Ray; Patty, Olivia; Acke, Els;
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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, Streptococcus equi subspecies equi, 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 S. equi to na?ve animals initiating new episodes of disease. Here, we report the analysis and visualization of phylogenomic and epidemiological data for 670 isolates of S. equi recovered from 19 different countries using a new core- genome multilocus sequence typing (cgMLST) web bioresource. Genetic relationships among all 670 S. equi 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 ?pizooties 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 S. equi and its close relative S. equi subspecies zooepidemicus that are recovered from horses and other animals, including humans, throughout the world. This article contains data hosted by Microreact.

Published in

Microbial genomics
2021, volume: 7, number: 3, article number: 000528

Authors' information

Mitchell, Catriona
Animal Health Trust
Steward, Karen F.
Animal Health Trust
Charbonneau, Amelia R. L.
Animal Health Trust
Walsh, Saoirse
Animal Health Trust
Wilson, Hayley
Animal Health Trust
Timoney, John F.
Gluck Equine Res Ctr
Wernery, Ulli
Central Veterinary Research Laboratory (CVRL)
Joseph, Marina
Central Veterinary Research Laboratory (CVRL)
Craig, David
Emirates Racing Author
van Maanen, Kees
Anim Hlth Serv GD
Hoogkamer- van Gennep, Annelies
Anim Hlth Serv GD
Leon, Albertine
Labeo Frank Duncombe
Witkowski, Lucjan
Warsaw University of Life Sciences
Rzewuska, Magdalena
Warsaw University of Life Sciences
Stefanska, Ilona
Warsaw University of Life Sciences
Zychska, Monika
Warsaw University of Life Sciences
van Loon, Gunther
Ghent University
Cursons, Ray
University of Waikato
Patty, Olivia
University of Waikato
Acke, Els
Massey University
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