Naturally occurring mutations in envelope mediate virulence of Usutu virus.

ABSTRACT: Usutu virus (USUV) is a mosquito-transmitted flavivirus that is closely related to West Nile virus. Recently, USUV emerged in Europe, where it has caused multiple bird die-off events and neuroinvasive disease in humans. Previously, we showed that USUV isolates from Africa cause significantly more severe disease than European isolates in mice. Sequence analysis revealed that the most virulent isolate (Uganda 2012) and the least virulent isolate (Netherlands 2016) differed by 21 amino acids across the viral polyprotein. Here, we sought to identify the viral determinants of and mechanisms for differential virulence. To accomplish this, we used our USUV reverse genetics system and bacteria-free cloning to generate chimeric viruses between Uganda 2012 and Netherlands 2016. Ifnar1^-/-

SUBMITTER: Vogt MB 

PROVIDER: S-EPMC12506040 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature