Impact of genetic diversity on biological characteristics of Usutu virus strains in Africa.

Impact of genetic diversity on biological characteristics of Usutu virus strains in Africa. Virus Res. 2019 Sep 12;:197753 Authors: Ndione MHD, Ndiaye EH, Thiam MS, Weidmann M, Faye M, Yamar, Benkaroun J, Faye O, Loucoubar C, Sembène PM, Diallo M, Sall AA, Faye O, Fall G Abstract Usutu virus (USUV) previously restricted to Africa where it caused mild infections, emerged in 2001 in Europe and caused more severe infections among birds and humans with neurological forms, suggesting an adaptation and increasing virulence. This evolution suggests the need to better understand USUV transmission patterns for assessing risks and to develop control strategies. Phylogenetic analysis conducted in Africa showed low genetic diversity of African USUV strains except for one human and the USUV subtype (USUVsub) strains, which exhibited a deletion in the 3'UTR and nucleotide substitutions throughout the genome. Here we analyzed their viral replication in vitro in mosquito and mammalian cells, and vector competence of Culex quinquefasciatus, compared to a reference strain. Growth kinetics of the different strains showed comparable replication rates however variations in replication and translation efficiency were observed. Vector competence analysis showed that all strains were able to infect Culex quinquefasciatus the main peridomestic Culex species in Africa, with detection of USUV viral genomes and infectious particles. Dissemination and transmiss...
Source: Virus Research - Category: Virology Authors: Tags: Virus Res Source Type: research