Characterization of an H6N1 avian influenza virus from an illegally imported product

Abstract Background : H6N1 is low pathogenic virus commonly found in wild and domestic birds across many continents. To investigate the infective status of imported food, we detected avian influenza virus (AIV) in illegally imported frozen food from international flight. Methods : The virus was isolated, the complete genome was sequenced, and the pathogenicity was tested. PQIATR/G was found in the motif of the HA cleavage site of the isolated strain, which conforms to the molecular characteristics of a low pathogenic AIV. The amino acid residues at positions 186, 190, 226, and 228 of the HA protein receptor binding sites were proline (P), valine (V), glutamine (Q), serine (S), respectively, exhibiting the molecular characteristics required to bind to human-like receptors. The SPF chicken test showed that the IVPI was 0 and the virus was a low pathogenic AIV. The infectious results in BALB/c mice showed that the isolate could be replicated in the lower respiratory tract of mice. Mice infected with a high dose of the virus displayed moderate weight loss but no obvious clinical symptoms. Results :The results of the sequence analysis showed that the avian influenza virus was of the H6N1 subtype, which shared the highest nucleotide identity with the AIV subtypes prevalent in Taiwan province. Conclusions : It is important to intensily monitor the illegal carrying.