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Pathogens (Basel, Switzerland)2016; 5(4); doi: 10.3390/pathogens5040061

Molecular Epidemiology and Spatio-Temporal Dynamics of the H3N8 Equine Influenza Virus in South America.

Abstract: Equine influenza virus (EIV) is considered the most important respiratory pathogen of horses as outbreaks of the disease lead to substantial economic losses. The H3N8 EIV has caused respiratory disease in horses across the world, including South American countries. Nucleotide and deduced amino acid sequences for the complete haemagglutinin gene of the H3N8 EIV detected in South America since 1963 were analyzed. Phylogenetic and Bayesian coalescent analyses were carried out to study the origin, the time of the most recent common ancestors (tMRCA), the demographic and the phylogeographic patterns of the H3N8 EIV. The phylogenetic analysis demonstrated that the H3N8 EIV detected in South America grouped in 5 well-supported monophyletic clades, each associated with strains of different origins. The tMRCA estimated for each group suggested that the virus was circulating in North America at least one year before its effective circulation in the South American population. Phylogenetic and coalescent analyses revealed a polyphyletic behavior of the viruses causing the outbreaks in South America between 1963 and 2012, possibly due to the introduction of at least 4 different EIVs through the international movement of horses. In addition, phylodynamic analysis suggested South America as the starting point of the spread of the H3N8 EIV in 1963 and showed migration links from the United States to South America in the subsequent EIV irruptions. Further, an increase in the relative genetic diversity was observed between 2006 and 2007 and a subsequent decline since 2009, probably due to the co-circulation of different lineages and as a result of the incorporation of the Florida clade 2 strain in vaccines, respectively. The observed data highlight the importance of epidemiological surveillance and the implementation of appropriate quarantine procedures to prevent outbreaks of the disease.
Publication Date: 2016-10-16 PubMed ID: 27754468PubMed Central: PMC5198161DOI: 10.3390/pathogens5040061Google Scholar: Lookup
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  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research aims to investigate the origin, evolution, and spread of the H3N8 Equine Influenza Virus (EIV) in South America. By analyzing the complete sequences of haemagglutinin gene of the virus, the researchers established that different strains of the virus are present in the region, and its outbreak patterns are driven by the international movement of horses.

Research Methodology

  • The research involved the detailed analysis of nucleotide and deduced amino acid sequences for the complete haemagglutinin gene of the H3N8 EIV detected in South America since 1963.
  • Phylogenetic and Bayesian coalescent analyses were utilized to study the origin and demographic patterns of the H3N8 EIV.
  • These analyses also enabled researchers to establish the most recent common ancestor (tMRCA) of the virus and deduce its phylogeographic patterns.

Key Findings

  • Researchers found that H3N8 EIV in South America could be classified into 5 monophyletic clades, each connected to strains originating from different locations.
  • The virus seemed to have circulated in North America a year prior to its prevalent circulation in South American horse population.
  • The EIV outbreak patterns in South American regions from 1963 to 2012 appeared to be polyphyletic, indicating that there were possibly at least 4 different EIV introductions, triggered by the international movement of horses.
  • The study further identified South America as the initial point of the H3N8 EIV spread in 1963, with links traced back to the United States for subsequent EIV irruptions.
  • A spike in relative genetic diversity of the virus was observed between 2006 and 2007, followed by a decline from 2009, likely due to the co-circulation of different lineages and the inclusion of the Florida clade 2 strain in vaccines.

Significance of the Study

  • The study highlights the necessity of consistent epidemiological surveillance and appropriate quarantine procedures to prevent disease outbreaks.
  • It also underscores the influence of international horse movement on EIV distribution and evolution, indicating a need to implement and strengthen biosecurity measures in horse trade.

Cite This Article

APA
Olguin Perglione C, Golemba MD, Torres C, Barrandeguy M. (2016). Molecular Epidemiology and Spatio-Temporal Dynamics of the H3N8 Equine Influenza Virus in South America. Pathogens, 5(4). https://doi.org/10.3390/pathogens5040061

Publication

ISSN: 2076-0817
NlmUniqueID: 101596317
Country: Switzerland
Language: English
Volume: 5
Issue: 4

Researcher Affiliations

Olguin Perglione, Cecilia
  • Instituto de Virología CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA), Dr. Nicolás Repetto y De Los Reseros s/n Hurlingham B1686LQF, Buenos Aires, Argentina. olguin.cecilia@inta.gob.ar.
Golemba, Marcelo D
  • Hospital de Pediatría S.A.M.I.C. "Prof. Dr. Juan P. Garrahan", Combate de los Pozos 1881, Ciudad Autónoma de Buenos Aires C1245AAM, Argentina. mgolemba@garrahan.gov.ar.
Torres, Carolina
  • Cátedra de Virología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, Ciudad Autónoma de Buenos Aires C1113AAD, Argentina. ctorres@ffyb.uba.ar.
  • CONICET, Av. Rivadavia 1917, Ciudad Autónoma de Buenos Aires C1033AAJ, Argentina. ctorres@ffyb.uba.ar.
Barrandeguy, Maria
  • Instituto de Virología CICVyA, Instituto Nacional de Tecnología Agropecuaria (INTA), Dr. Nicolás Repetto y De Los Reseros s/n Hurlingham B1686LQF, Buenos Aires, Argentina. barrandeguy.maria@inta.gob.ar.
  • Escuela de Veterinaria, Universidad del Salvador, Viamonte 1856, Ciudad Autónoma de Buenos Aires C1056ABB, Argentina. barrandeguy.maria@inta.gob.ar.

Conflict of Interest Statement

The authors declared no conflict of interest.

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