First human case of influenza A/H10N3 virus infection

On May 28, 2021 a resident of the City of Zhenjiang in Jiangsu Province, China, was diagnosed with an influenza A/H10N3 virus infection. This is the first human case of infection with a low pathogenic avian influenza virus of this subtype. How the person was infected is unclear. There is no evidence that the virus spreads easily between humans. A/H10 influenza viruses are abundant in wild birds globally, and occasionally transmit to poultry.

The whole genome sequence of the virus, A/Jiangsu/428/2021, was released rapidly via the GISAID Initiative by the Jiangsu Provincial Center for Disease Control and Prevention in Nanjing (EPI_ISL_2379892).

Novel H10N3 receptor binding pocket comparison with human infecting H10N8 

HA receptor binding pocket of a human infecting H10N8 (PDB:4QY2 dx.doi.org/10.1038/ncomms6600) with the differences of the new H10N3 highlighted in red and green. The human host receptor is shown in yellow. A unique G238S (alternative numbering: H3=228 H1=225) mutation that is known in other subtypes to favor 2,6 (human) over 2,3 (avian) receptors (e.g. H3 G228S in dx.doi.org/10.1128/jvi.74.18.8502-8512.2000) and S at this position is also present in human seasonal H3N2.

Analysis by Sebastian Maurer-Stroh for GISAID data submitters