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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
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Main Article

1These first authors contributed equally to this article.

2These authors contributed equally to this article.

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