Evaluation of a mouse model for the West Nile virus group for the purpose of determining viral pathotypes

• DOI: 10.1099/vir.0.063537-0
• Publication Date: 2014-04-03T05:02:32Z
• Authors: John Bingham; Jean Payne; Jennifer Harper; Leah Frazer; Sarah Eastwood; Susanne Wilson; Sue Lowther; Ross Lunt; Simone Warner; Mary Carr; Roy A. Hall; Peter A. Durr
• Keywords: Flavivirus; Seroconversion

West Nile virus (WNV; family Flaviviridae ; genus Flavivirus ) group members are an important cause of viral meningoencephalitis in some areas the world. They exhibit marked variation pathogenicity, with lineages (such as those from North America) causing high prevalence severe neurological disease, whilst others Australian Kunjin virus) rarely disease. The aim this study was to characterize WNV disease a mouse model and elucidate pathogenetic features that distinguish variation. Tenfold dilutions five strains (New York 1999, MRM16 three horse isolates WNV-Kunjin: Boort two 2011 outbreak) were inoculated into mice by intraperitoneal route. All induced different proportions infected mice. NY99 most pathogenic, intermediate pathogenicity KUNV-MRM16 least, mostly asymptomatic seroconversion. Infectivity, but not related challenge dose. Using cluster analysis recorded clinical signs, histopathological lesions antigen distribution scores, cases could be classified groups corresponding severity. Metrics determining pathotype included signs (paralysis seizures), meningoencephalitis, brain scores replication extra-neural tissues. Whereas all had antigen, WNV-Kunjin viruses only occasionally outside nervous system. We conclude useful tool for assessment WNVs.