Co-Infection: Simultaneous Detection of West Nile Virus and Usutu Virus in Birds from Germany. Usutu virus/West Nile virus co-infections in birds

The emergence of West Nile virus (WNV) and Usutu virus (USUV) in Europe resulted in significant outbreaks leading to avifauna mortality and human infections. These Flaviviruses have overlapping geographical, host and vector ranges and are often co-circulating. In Germany, a nationwide wild bird surveillance network was established to monitor these zoonotic arthropod-borne viruses in migratory and resident birds. In the framework of this surveillance system, co-infections with WNV and USUV RNA were detected in six perished birds collected in 2018 and 2019. Genomic sequencing and phylogenetic analyses were applied to classify the WNV and USUV strains.