The evolution of human influenza A viruses from 1999 to 2006: a complete genome study.

摘要: Knowledge about the complete genome constellation of seasonal influenza A viruses from different countries is valuable for monitoring and understanding evolution migration strains. Few sequences Europe are publicly available at present time there have been few longitudinal studies human viruses. We studied circulating H3N2, H1N1 H1N2 1999 to 2006, we analysed 234 Danish characterised 24 genomes. H3N2 was prevalent strain in Denmark during study period, but dominated 2000–2001 season. were first observed 2002–2003. After years little genetic change 2005–2006 season presented greater variability than before. This indicates that evolving soon likely be again. Generally, haemagglutinin (HA) formed phylogenetic clusters. Different lineages co-circulating within same also observed. The has stochastic, influenced by small "jumps" distance rather constant drift, especially with introduction Fujian-like Also evolutionary stasis-periods which might indicate well fit gene reassortments between seasons. None genes strong positive selection pressure. antigenic site B HA preferred period probably because masked glycosylations. Substitutions CTL-epitopes coding neuraminidase (NA), polymerase acidic protein (PA), matrix 1 (M1), non-structural (NS1) nucleoprotein (NP) N-linked glycosylation pattern varied isolates 2004 2006 highly glycosylated ten predicted sequons HA, highest amount glycosylations this period. our knowledge characterise genomes over a seven 2006. More precise strains may implications predicting following thereby better matching vaccine composition.