• getoffthedrugsdude
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    3 days ago

    The viral genome sequence obtained from a tracheal-aspirate specimen collected on November 9 (8 days after the onset of symptoms) was reconstructed as described previously.3 The virus was typed as clade 2.3.4.4b, genotype D1.1,4 most closely related to viruses detected in wild birds in British Columbia around the same time (Fig. S2). Markers of adaptation to humans were detected in the tracheal-aspirate specimen collected on November 9: the E627K mutation was detected (52% allele frequency) in the polymerase basic 2 (PB2) gene product, and analysis of the H5 hemagglutinin (HA) gene yielded ambiguous calls in the codons for amino acid residues E186 (E190 according to H3 mature HA numbering) — 28% allele frequency for E186D — and Q222 (Q226 according to H3 mature HA numbering) — 35% allele frequency for Q222H. The mutations in the H5 HA gene have previously been shown to increase binding to α2-6–linked sialic acids, which act as receptors that facilitate viral entry into cells in the human respiratory tract and enable viral replication.5