ERVW-1 and infection: To evaluate the infection potential of the Bangladeshi H9N2 viruses, we undertook a preliminary study involving two distinct Bangladeshi H9N2 viruses (env/Bd/10306 and ck/Bd/10450) with differing molecular genotypes harboring various mammalian host-specific substitutions throughout their genomes, especially in the receptor-binding site of the HA glycoprotein (Table 2).