And α2,6-sa ( 9 ). the equilibrium dissociation constant for 3′-sialyl-n-acetyllactosamine is 12.2 (sd ± 0.7 nmol/l) and for 6′-sialyl-n-acetyllactosamine is 43.3 (sd ± 2.8 nmol/l) (appendix). these values show that a/common gull/saratov/1676/2018 has prevalent affinity for the avi- an-like receptor with lower, but increased, affinity for the human-like receptor, compared with h5n1 strain a/rook/ chany/32/2015 clade 2.3.2.1.c. analysis of homology of a/common gull/sara- tov/1676/2018 with h5n6 strains available from gisaid showed that all 8 gene segments clustered with human h5n6 strains isolated in southeast china in 2018. we noted 99% homology with human strain a/guangxi/32797/2018 for all genes, a genetic similarity that raises the question of which pathway led to the spread of the virus. we be- lieve a/common gull/saratov/1676/2018 was transferred to eastern russia through northeast siberia, where hpai h5n8 clade 2.3.4.4.a was detected in 2018 ( 10 ), the same pathway through which h5n8 virus was transferred from southeast asia to europe. these viral pathogens could be spread by migratory birds over long distances along fly- ways from southern china to southwestern russia during a migration season. our study indicates that emerging h5n6 viruses are a potential threat to public health