The panorama of the diversity of H5 subtype influenza viruses.
To elucidate the global diversity of H5 influenza viruses from a dynamic view, haemagglutinin (HA) sequences of 170 isolates were selected and analyzed in this study. Our results showed that H5 influenza isolates could be divided into two distinct lineages that circulated in the Eastern Hemisphere and the Western Hemisphere, respectively. This may be due to the separate migration routes and habitats of birds in the two hemispheres. The two distinct lineages, having existed at least for decades, possibly began divergence in 1850s. Each of the two distinct HA lineages could be further divided into some sublineages, but there was little correlation between the minor lineages and their isolation places, isolation time, neuraminidase subtypes, host species or virulence. The panorama of the diversity of H5 influenza viruses presented here integrated all known H5 epidemics including the current severe H5N1 avian epidemics in the Eastern Hemisphere and suggested that H5 virulent viruses could originate from multiple sublineages and associate with multiple NA subtypes. Our study provided a framework for the studies on the evolution and epidemiology of H5 influenza viruses.
Ma
Hong-Chao
HC
Chinese Center for Animal Health and Epidemiology, Nanjing Road 369#, Qingdao 266032, China.
Chen
Ji-Ming
JM
Chen
Ji-Wang
JW
Sun
Ying-Xue
YX
Li
Jin-Ming
JM
Wang
Zhi-Liang
ZL
D014644:Genetic Variation; D053124:Influenza A Virus, H5N1 Subtype / Q000235:genetics; D053125:Influenza A Virus, H5N2 Subtype / Q000235:genetics; D009980:Influenza A virus / Q000145:classification / Q000235:genetics*; D008969:Molecular Sequence Data; D009439:Neuraminidase / Q000145:classification / Q000235:genetics; D010802:Phylogeny; D020539:Sequence Analysis, Protein
D009439:Neuraminidase