Immunogen: in vivo expressed HA (amino acid 1-345) of influenza virus avian flu / bird flu strain (A/ Bar-headed Goose/ Qinghai/12/05) (H5N1) (GenBank Accession No. ABE68927). Specificity: Reacts with human and avian H5 (H5N1). Cross-reactivity to other HA proteins not tested.