Phylogenetic Analysis of the 2020 West Nile Virus (WNV) Outbreak in Andalusia (Spain)

• Main Authors: Carlos S. Casimiro-Soriguer, Javier Perez-Florido, Jose L. Fernandez-Rueda, Irene Pedrosa-Corral, Vicente Guillot-Sulay, Nicola Lorusso, Luis Javier Martinez-Gonzalez, Jose M. Navarro-Marí, Joaquin Dopazo, Sara Sanbonmatsu-Gámez
• Format: Article
• Language: English
• Published: MDPI AG 2021-05-01
• Series: Viruses
• Subjects: West Nile Virus; outbreak; meningoencephalitis; epidemiology; phylogeny; whole genome sequencing
• Online Access: https://www.mdpi.com/1999-4915/13/5/836

During recent decades West Nile Virus (WNV) outbreaks have continuously occurred in the Mediterranean area. In August 2020 a new WNV outbreak affected 71 people with meningoencephalitis in Andalusia and six more cases were detected in Extremadura (south-west of Spain), causing a total of eight deaths. The whole genomes of four viruses were obtained and phylogenetically analyzed in the context of recent outbreaks. The Andalusian viral samples belonged to lineage 1 and were relatively similar to those of previous outbreaks which occurred in the Mediterranean region. Here we present a detailed analysis of the outbreak, including an extensive phylogenetic study. As part on this effort, we implemented a local Nextstrain server, which has become a constituent piece of regional epidemiological surveillance, wherein forthcoming genomes of environmental samples or, eventually, future outbreaks, will be included.