Skip directly to site content Skip directly to page options Skip directly to A-Z link Skip directly to A-Z link Skip directly to A-Z link

Disclaimer: Early release articles are not considered as final versions. Any changes will be reflected in the online version in the month the article is officially released.

Volume 31, Number 1—January 2025
Research Letter

Equine Encephalomyelitis Outbreak, Uruguay, 2023–2024

Sandra Frabasile1, Noelia Morel1, Ramiro Pérez1, Lucía Moreira Marrero1, Analia Burgueño1, María Noel Cortinas, Lucía Bassetti, Raúl Negro, Sirley Rodríguez, Victoria Bórmida, Valeria Gayo, Victor Costa de Souza, Felipe Gomes Naveca, Mariela Martínez Gómez, Lionel Gresh, Jairo Mendez-Rico, Héctor Chiparelli2, and Adriana Delfraro2Comments to Author 
Author affiliation: Universidad de la República, Montevideo, Uruguay (S. Frabasile, L. Moreira Marrero, A. Delfraro); Ministerio de Salud Pública, Montevideo (N. Morel, A. Burgueño, M.N. Cortinas, V. Bórmida, H. Chiparelli); Ministerio de Ganadería Agricultura y Pesca, Montevideo (R. Pérez, L. Bassetti, R. Negro, S. Rodríguez, V. Gayo); Instituto Leônidas e Maria Deane, Manaus, Brazil (V. Costa de Souza, F.G. Naveca); Instituto Oswaldo Cruz, Rio de Janeiro, Brazil (F.G. Naveca); Pan American Health Organization, Washington, DC, USA (M. Martínez Gómez, L. Gresh, J. Mendez-Rico)

Main Article

Figure 2

Maximum-likelihood phylogenetic analysis of alphavirus sequences from South and North America and WEEV sequences described in investigation of equine encephalomyelitis outbreak, Uruguay. A) Phylogeny based on partial nonstructural protein 4 gene sequences. B) Phylogeny based on complete sequences. GenBank accession numbers are provided. Subclades are assigned as previously described (5,6). Clades including reference sequences from other alphaviruses were collapsed for better visualization. Red, sequences from Uruguay 2023–2024; orange, 2009 sequences; blue, sequences from Argentina; green, sequences from Brazil. Branch numbers are approximate likelihood ratio supports. Scale bar indicates substitutions per site. CHIKV, chikungunya virus; EEEV, Eastern equine encephalomyelitis virus; MADV, Madariaga virus; MDPV, Mosso das Pedras virus; MIDV, Middelburg virus; MAYV, Mayaro virus; MUCV, Mucambo virus; OCKV, Ockelbo virus; ONYV, o'nyong-nyong virus; RNV, Rio Negro virus; SINDV, Sindbis virus; VEEV, Venezuelan equine encephalitis virus; WEEV, Western equine encephalomyelitis virus.

Figure 2. Maximum-likelihood phylogenetic analysis of alphavirus sequences from South and North America and WEEV sequences described in investigation of equine encephalomyelitis outbreak, Uruguay. A) Phylogeny based on partial nonstructural protein 4 gene sequences. B) Phylogeny based on complete sequences. GenBank accession numbers are provided. Subclades are assigned as previously described (5,6). Clades including reference sequences from other alphaviruses were collapsed for better visualization. Red, sequences from Uruguay 2023–2024; orange, 2009 sequences; blue, sequences from Argentina; green, sequences from Brazil. Branch numbers are approximate likelihood ratio supports. Scale bar indicates substitutions per site. CHIKV, chikungunya virus; EEEV, Eastern equine encephalomyelitis virus; MADV, Madariaga virus; MDPV, Mosso das Pedras virus; MIDV, Middelburg virus; MAYV, Mayaro virus; MUCV, Mucambo virus; OCKV, Ockelbo virus; ONYV, o'nyong-nyong virus; RNV, Rio Negro virus; SINDV, Sindbis virus; VEEV, Venezuelan equine encephalitis virus; WEEV, Western equine encephalomyelitis virus.

Main Article

References
  1. Sánchez-Seco  MP, Rosario  D, Quiroz  E, Guzmán  G, Tenorio  A. A generic nested-RT-PCR followed by sequencing for detection and identification of members of the alphavirus genus. J Virol Methods. 2001;95:153–61. DOIPubMedGoogle Scholar
  2. Moreira Marrero  L, Botto Nuñez  G, Frabasile  S, Delfraro  A. Alphavirus identification in neotropical bats. Viruses. 2022;14:269. DOIPubMedGoogle Scholar
  3. Katoh  K, Rozewicki  J, Yamada  KD. MAFFT online service: multiple sequence alignment, interactive sequence choice and visualization. Brief Bioinform. 2019;20:1160–6. DOIPubMedGoogle Scholar
  4. Guindon  S, Dufayard  JF, Lefort  V, Anisimova  M, Hordijk  W, Gascuel  O. New algorithms and methods to estimate maximum-likelihood phylogenies: assessing the performance of PhyML 3.0. Syst Biol. 2010;59:307–21. DOIPubMedGoogle Scholar
  5. Bergren  NA, Auguste  AJ, Forrester  NL, Negi  SS, Braun  WA, Weaver  SC. Western equine encephalitis virus: evolutionary analysis of a declining alphavirus based on complete genome sequences. J Virol. 2014;88:9260–7. DOIPubMedGoogle Scholar
  6. Bergren  NA, Haller  S, Rossi  SL, Seymour  RL, Huang  J, Miller  AL, et al. “Submergence” of Western equine encephalitis virus: Evidence of positive selection argues against genetic drift and fitness reductions. PLoS Pathog. 2020;16:e1008102. DOIPubMedGoogle Scholar
  7. Delfraro  A, Burgueño  A, Morel  N, González  G, García  A, Morelli  J, et al. Fatal human case of Western equine encephalitis, Uruguay. Emerg Infect Dis. 2011;17:952–4. DOIPubMedGoogle Scholar
  8. Somma Moreira  RE, Campione-Piccardo  J, Russi  JC, Hortal de Giordano  M, Bauzá  CA, Peluffo  G, et al. Arbovirus en el Uruguay. Arch Pediatr Urug. 1970;41:359–63.
  9. Burgueño  A, Frabasile  S, Díaz  LA, Cabrera  A, Pisano  MB, Rivarola  ME, et al. Genomic characterization and seroprevalence studies on alphaviruses in Uruguay. Am J Trop Med Hyg. 2018;98:1811–8. DOIPubMedGoogle Scholar

Main Article

1These first authors contributed equally to this article.

2These authors contributed equally to this article.

Page created: October 16, 2024
Page updated: October 23, 2024
Page reviewed: October 23, 2024
The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors' affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.
file_external