A novel reassortant H2N3 influenza virus isolated from China.

Objective: To analyze the genetic composition of a novel H2N3 virus isolate identified from a duck cage swab in a live poultry market (LPM) in 2009 in Guangdong province of China.

Methods: PCR-positive specimens were inoculated into embryonated chicken eggs and subtyped by conventional RT-PCR. All segments of the virus A/environment/Guangdong/2/2009 were sequenced, and phylogenetic trees were constructed and analyzed.

Results: The genes of this virus belong to Eurasian-lineage avian viruses. The virus is a reassortant with the HA gene from an H2N2 virus and the NA gene from an H5N3 virus. The PB1, PB2, and NP genes were from an H4N6 virus, the PA was from an H3N8 virus, the M gene was from an H1N3 virus, and the NS gene was from an H10N6 virus.

Conclusion: A novel avian-origin reassortant H2N3 influenza virus was detected in a live poultry market. Its potential impacts and evolution should be closely monitored.