Phylogenetic Analysis of the First Isolate of Polish H1N2 Swine Influenza Virus

Phylogenetic analysis of the genes determining influenza virus subtype - haemagglutinin (HA) and neuraminidase (NA), was performed. The results showed that the Polish H1N2 isolate (A/Swine/Poland15817/2011) was reassortant of human-like swine H1N1 and human-like swine H3N2 origin. The novel isolate was presented to have a close phylogenic relationship with one of the latest European isolates of H1N2 (A/SW/Gent/102/2007 and A/SW/Hungary/13509/2007). Our evolutionary analyses also suggested that the HA and NA genes evolved in a significantly higher rate of synonymous substitutions after they were introduced from human to swine and established the European H1N2 swine lineage.