The potential for viruses to reassort themselves and the risks that this potential brings to us in terms of H5N1 finding an opportunity to mutate and pose that threat is highlighted here where H5N2 has indeed shown that it has undergone this reassortment with H5N1, in China.

Four new H5N2 strains identified in China
Chinese researchers detailed four new strains of H5N2 avian flu viruses in PLoS One yesterday, all of which were able to replicate in ducks and mice. The team analyzed the evolution and pathogenicity of the strains, which were isolated from apparently healthy poultry in H5N1-endemic parts of China. Two of these viruses developed when clade 2.3.4 H5N1 viruses reassorted and acquired novel neuraminidase and nonstructural protein genes.

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