FLU NEWS SCAN: New H5N2 strains, H1N1 vaccine events

Sep 26, 2012

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. The other two isolates have a hemagglutinin gene from clade 7 H5[N1? Seems odd to list a clade without the full subtype designation] viruses and other genes from endemic H9N2 viruses or other subtypes. "All of these 4 viruses were able to replicate in domestic ducks and mice without prior adaptation," the authors conclude, adding that their findings highlight the potential threat the viruses pose to both animals and humans.
Sep 25 PLoS One report

Study: Adjuvants in H1N1 vaccine did not increase autoimmune events
Adjuvanted and nonadjuvanted pandemic 2009 H1N1 (pH1N1) vaccines were associated with similar instances of autoimmune disorders (AID) in Europe, and these adverse events were not unexpectedly frequent, scientists from the European Medicines Agency reported today in Vaccine. The group, based in London, analyzed data on adverse events reported to EudraVigilance from Oct 1, 2009, to Dec 31, 2010, for Guillain-Barre syndrome (GBS), idiopathic thrombocytopenic purpura, and acute disseminated encephalomyelitis. Of the 50,221 adverse reactions reported for pH1N1 vaccines (adjuvanted, 46,173; nonadjuvanted, 4,048), 314 were for AID (adjuvanted, 276; nonadjuvanted, 38). GBS accounted for the most AID reports, at 125 (adjuvanted, 109; nonadjuvanted, 16). Reporting rates for all AID were 6.87 per million doses for adjuvanted vaccines and 9.98 per million doses for nonadjuvanted vaccines. In a restricted analysis based on diagnostic certainty, causal relationship, and plausible temporal association, those numbers fell to 3.01 and 3.94, respectively. "These results do not suggest a difference in the reporting of AID between adjuvanted and non-adjuvanted [pH1N1] vaccines," the authors concluded, adding that "reporting rates were generally within expected background rates."
Sep 26 Vaccine abstract

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