Figure 1. Histopathology of the brain associated with RusV infection in red-necked wallabies: (a) Non-suppurative meningoencephalitis with marked perivascular cuffing, H&E stain.(b) RNA ISH, detection of RusV specific RNA in neuronal bodies and processes, fast red as chromogenic labeling, Mayer’s hematoxylin counter stain. (c) Immunohistochemistry for iba-1 as a marker for microglia and macrophages revealing few microglial nodules (asterisk). (d) Immunohistochemistry for CD3 as a T cell marker on a consecutive slide to (e), indicating perivascular lymphocytic cuffing consisting of numerous T cells (arrow) and microglial nodules containing few interspersed T cells (arrow head). (e) and(f) Immunohistochemistry for GFAP as a marker for astrocyte detection, indicating (e) plump appearance as sign of activation of astrocytes in one region and in comparison, (f)normal appearance of astrocytes in other regions. (c)- (f) AEC for chromogen labeling, Mayer’s hematoxylin counter stain. Scale bar 50 µm (a)-(b) and (e)-(f), 100µm (c) and (d).
Figure 2. Current geographic distribution of RusV infections in Germany in red-necked wallabies. Further cases of RusV infections occurred in other zoo and wildlife species in the region of case 1 of this study.
Figure 3. Phylogenetic analysis of partial RusV E1-encoding sequences (715 nucleotides, representing genome positions 8,208 to 8,922 of the RusV reference genome MN552442.2) was performed using the Neighbor-Joining algorithm and Jukes-Cantor distance model in Geneious 11.1.5. RusV sequences from red-necked wallabies determined during this study are depicted in bold. Values at branches represent support in 1,000 bootstrap replicates. Only bootstrap values ≥70 at major branches are shown. GER: Germany; BB = Brandenburg; MV: Mecklenburg-Western Pomerania.