https://orcid.org/0000-0002-5809-0729
Figures & data
Figure 1. Histopathology and immunohistochemical findings in the brain tissue of the seals. The cerebellum of the H5N1 infected seal from The Netherlands (case 1) showed the following changes: (A) An acute non-suppurative and necrotising encephalitis with mild perivascular lympho-histiocytic infiltration (circle), diffuse gliosis of the adjacent neuroparenchyma (molecular layer), necrosis of Purkinje cells (arrow) and necrosis of inner granular cells (arrowheads); (B) Abundant intralesional AIV nucleoprotein in cells of the inner granular layer (arrowheads) and within the adjacent neuropil. The brain of the H5N1 infected seal from Germany (case 2) showed: (C) Moderate lympho-histiocytic leptomeningitis. (D) Moderate non-suppurative and necrotising encephalitis with perivascular lympho-histiocytic cuffing and vasculitis (arrows), gliosis and necrosis (arrowheads) in the adjacent parenchyma. E. Abundant AIV nucleoprotein in neuronal nuclei, perikarya and processes (arrows) and in various glial cells (arrowheads) of the cerebrum.
Figure 2. Phylogenetic relationships of concatenated consensus whole-HPAIV H5N1 sequences from The Netherlands and Germany in 2022–2023. The complete genome sequence of H5N1 strains derived from infected seals in Germany and The Netherlands were compared to sympatric avian strains belonging to the clade 2.3.4.4b of H5. Sequences were obtained from the EpiFluTM GISAID database. Isolate identifier contains the following information: Accession number, virus designation, subtype and collection date. Maximum likelihood (ML) trees were calculated with RAxML (v8.2.11) utilising model GTR GAMMA with rapid bootstrapping. Scale bar indicates nucleotide substitutions per site. Bootstrap values below 70 are not displayed.
