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
Volume 30, Number 9—September 2024
Research

Molecular Epidemiology of Western Equine Encephalitis Virus, South America, 2023–2024

Aline Scarpellini Campos, Ana Claúdia Franco, Fernanda M. Godinho, Rosana Huff, Darlan S. Candido, Jader da Cruz Cardoso, Xinyi Hua, Ingra M. Claro, Paola Morais, Carolina Franceschina, Thales de Lima Bermann, Franciellen Machado dos Santos, Milena Bauermann, Tainá Machado Selayaran, Amanda Pellenz Ruivo, Cristiane Santin, Juciane Bonella, Carla Rodenbusch, José Carlos Ferreira, Scott C. Weaver, Vilar Ricardo Gewehr, Gabriel Luz Wallau, William M. de Souza1Comments to Author , and Richard Steiner Salvato1Comments to Author 
Author affiliations: Secretaria de Saúde do Estado do Rio Grande do Sul, Porto Alegre, Brazil (A.S. Campos, F.M. Godinho, R. Huff, J. da Cruz Cardoso, P. Morais, C. Franceschina, F. Machado dos Santos, M. Bauermann, T.M. Selayaran, A.P. Ruivo, R.S. Salvato); Universidade Federal do Rio Grande do Sul, Porto Alegre (A.C. Franco, T. de L. Bermann, R.S. Salvato); Imperial College London, London, UK (D.S. Candido); University of Kentucky, Lexington, Kentucky, USA (X. Hua, I.M. Claro, W.M. de Souza); Secretaria de Agricultura do Estado do Rio Grande do Sul, Porto Alegre (C. Santin, J. Bonella, C. Rodenbusch, J.C. Ferreira, V.R. Gewehr); University of Texas Medical Branch, Galveston, Texas, USA (S.C. Weaver); Fundação Oswaldo Cruz, Recife, Brazil (G.L. Wallau); Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany (G.L. Wallau)

Main Article

Figure 1

Western equine encephalitis cases in Argentina, Uruguay, and Brazil. A) Cumulative western equine encephalitis laboratory-confirmed cases in Argentina and Uruguay reported to the Pan American Health Organization (PAHO) during October 2023‒June 2024 (9). B) Locations of deaths among horses in Rio Grande do Sul state, Brazil, that tested positive (blue) and negative (yellow) for WEEV by RT-PCR during December 2023‒April 2024. The cases were identified by our molecular epidemiology study in Barra do Quaraí on December 21, 2023 (EQ1090), in Uruguaiana on December 28, 2023 (EQ1122), and in Jaguarão on January 30, 2024 (EQ237). WEEV, western equine encephalitis virus.

Figure 1. Western equine encephalitis cases in Argentina, Uruguay, and Brazil. A) Cumulative western equine encephalitis laboratory-confirmed cases in Argentina and Uruguay reported to the Pan American Health Organization (PAHO) during October 2023‒June 2024 (9). B) Locations of deaths among horses in Rio Grande do Sul state, Brazil, that tested positive (blue) and negative (yellow) for WEEV by RT-PCR during December 2023‒April 2024. The cases were identified by our molecular epidemiology study in Barra do Quaraí on December 21, 2023 (EQ1090), in Uruguaiana on December 28, 2023 (EQ1122), and in Jaguarão on January 30, 2024 (EQ237). WEEV, western equine encephalitis virus.

Main Article

References
  1. 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
  2. Calisher  CH, Monath  TP, Mitchell  CJ, Sabattini  MS, Cropp  CB, Kerschner  J, et al. Arbovirus investigations in Argentina, 1977-1980. III. Identification and characterization of viruses isolated, including new subtypes of western and Venezuelan equine encephalitis viruses and four new bunyaviruses (Las Maloyas, Resistencia, Barranqueras, and Antequera). Am J Trop Med Hyg. 1985;34:956–65. DOIPubMedGoogle Scholar
  3. Avilés  G, Sabattini  MS, Mitchell  CJ. Transmission of western equine encephalomyelitis virus by Argentine Aedes albifasciatus (Diptera: Culicidae). J Med Entomol. 1992;29:850–3. DOIPubMedGoogle Scholar
  4. 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
  5. Cohen  R, O’Connor  RE, Townsend  TE, Webb  PA, McKey  RW. Western equine encephalomyelitis; clinical observations in infants and children. J Pediatr. 1953;43:26–34. DOIPubMedGoogle Scholar
  6. Bartelloni  PJ, McKinney  RW, Calia  FM, Ramsburg  HH, Cole  FE Jr. Inactivated western equine encephalomyelitis vaccine propagated in chick embryo cell culture. Clinical and serological evaluation in man. Am J Trop Med Hyg. 1971;20:146–9. DOIPubMedGoogle Scholar
  7. Avilés  G, Bianchi  TI, Daffner  JF, Sabattini  MS. [Post-epizootic activity of Western equine encephalitis virus in Argentina] [in Spanish]. Rev Argent Microbiol. 1993;25:88–99.PubMedGoogle Scholar
  8. 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
  9. Pan American Health Organization. Western equine encephalitis in the Region of the Americas [in Spanish]. 2024 [cited 27 Jul 2024]. https://shiny.paho-phe.org/encephalitis
  10. Consoli  RAGB, Lourenço de Oliveira  R. Main mosquitoes of health importance in Brazil [in Portuguese]. 2nd edition. Rio de Janeiro: FIOCRUZ; 1998.
  11. Forattini  OP. Medical culicidology. Vol 2. Identification, biology, epidemiology. Sao Paulo: University of Sao Paulo; 2002.
  12. Muñoz-Gamba  AS, Laiton-Donato  K, Perdomo-Balaguera  E, Castro  LR, Usme-Ciro  JA, Parra-Henao  G. Molecular characterization of mosquitoes (Diptera: Culicidae) from the Colombian rainforest. Rev Inst Med Trop São Paulo. 2021;63:e24. DOIPubMedGoogle Scholar
  13. Lambert  AJ, Martin  DA, Lanciotti  RS. Detection of North American eastern and western equine encephalitis viruses by nucleic acid amplification assays. J Clin Microbiol. 2003;41:379–85. DOIPubMedGoogle Scholar
  14. Lanciotti  RS, Kerst  AJ. Nucleic acid sequence-based amplification assays for rapid detection of West Nile and St. Louis encephalitis viruses. J Clin Microbiol. 2001;39:4506–13. DOIPubMedGoogle Scholar
  15. Naveca  FG, Nascimento  VAD, Souza  VC, Nunes  BTD, Rodrigues  DSG, Vasconcelos  PFDC. Multiplexed reverse transcription real-time polymerase chain reaction for simultaneous detection of Mayaro, Oropouche, and Oropouche-like viruses. Mem Inst Oswaldo Cruz. 2017;112:510–3. DOIPubMedGoogle Scholar
  16. Wadhwa  A, Wilkins  K, Gao  J, Condori Condori  RE, Gigante  CM, Zhao  H, et al. A pan-lyssavirus Taqman real-time RT-PCR assay for the detection of highly variable rabies virus and other lyssaviruses. PLoS Negl Trop Dis. 2017;11:e0005258. DOIPubMedGoogle Scholar
  17. Dezordi  FZ, Neto  AMDS, Campos  TL, Jeronimo  PMC, Aksenen  CF, Almeida  SP, et al.; On Behalf Of The Fiocruz Covid-Genomic Surveillance Network. ViralFlow: a versatile automated workflow for SARS-CoV-2 genome assembly, lineage assignment, mutations and intrahost variant detection. Viruses. 2022;14:217. DOIPubMedGoogle Scholar
  18. Katoh  K, Standley  DM. MAFFT multiple sequence alignment software version 7: improvements in performance and usability. Mol Biol Evol. 2013;30:772–80. DOIPubMedGoogle Scholar
  19. Martin  DP, Murrell  B, Golden  M, Khoosal  A, Muhire  B. RDP4: Detection and analysis of recombination patterns in virus genomes. Virus Evol. 2015;1:vev003. DOIPubMedGoogle Scholar
  20. Minh  BQ, Schmidt  HA, Chernomor  O, Schrempf  D, Woodhams  MD, von Haeseler  A, et al. IQ-TREE 2: new models and efficient methods for phylogenetic inference in the genomic era. Mol Biol Evol. 2020;37:1530–4. DOIPubMedGoogle Scholar
  21. Kalyaanamoorthy  S, Minh  BQ, Wong  TKF, von Haeseler  A, Jermiin  LS. ModelFinder: fast model selection for accurate phylogenetic estimates. Nat Methods. 2017;14:587–9. DOIPubMedGoogle Scholar
  22. Hoang  DT, Chernomor  O, von Haeseler  A, Minh  BQ, Vinh  LS. UFBoot2: improving the ultrafast bootstrap approximation. Mol Biol Evol. 2018;35:518–22. DOIPubMedGoogle Scholar
  23. Rambaut  A, Lam  TT, Max Carvalho  L, Pybus  OG. Exploring the temporal structure of heterochronous sequences using TempEst (formerly Path-O-Gen). Virus Evol. 2016;2:vew007. DOIPubMedGoogle Scholar
  24. Suchard  MA, Lemey  P, Baele  G, Ayres  DL, Drummond  AJ, Rambaut  A. Bayesian phylogenetic and phylodynamic data integration using BEAST 1.10. Virus Evol. 2018;4:vey016. DOIPubMedGoogle Scholar
  25. Gill  MS, Lemey  P, Faria  NR, Rambaut  A, Shapiro  B, Suchard  MA. Improving Bayesian population dynamics inference: a coalescent-based model for multiple loci. Mol Biol Evol. 2013;30:713–24. DOIPubMedGoogle Scholar
  26. Ayres  DL, Darling  A, Zwickl  DJ, Beerli  P, Holder  MT, Lewis  PO, et al. BEAGLE: an application programming interface and high-performance computing library for statistical phylogenetics. Syst Biol. 2012;61:170–3. DOIPubMedGoogle Scholar
  27. Weaver  SC, Kang  W, Shirako  Y, Rumenapf  T, Strauss  EG, Strauss  JH. Recombinational history and molecular evolution of western equine encephalomyelitis complex alphaviruses. J Virol. 1997;71:613–23. DOIPubMedGoogle Scholar
  28. Mossel  EC, Ledermann  JP, Phillips  AT, Borland  EM, Powers  AM, Olson  KE. Molecular determinants of mouse neurovirulence and mosquito infection for Western equine encephalitis virus. PLoS One. 2013;8:e60427. DOIPubMedGoogle Scholar
  29. Brault  AC, Fang  Y, Reisen  WK. Multiplex qRT-PCR for the detection of western equine encephalomyelitis, St. Louis encephalitis, and West Nile viral RNA in mosquito pools (Diptera: Culicidae). J Med Entomol. 2015;52:491–9. DOIPubMedGoogle Scholar
  30. Cardoso  J, Corseuil  E, Barata  JMS. Culicinae (Diptera, Culicidae) occurring in the state of Rio Grande do Sul, Brasil [in Portuguese]. Rev Bras Entomol. 2005;49:275–87. DOIGoogle Scholar
  31. de Souza  WM, Weaver  SC. Effects of climate change and human activities on vector-borne diseases. Nat Rev Microbiol. 2024;22:476–91. DOIPubMedGoogle Scholar

Main Article

1These senior authors contributed equally to this article.

Page created: July 25, 2024
Page updated: August 22, 2024
Page reviewed: August 22, 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