The evolution of human influenza viruses

✍ Scribed by Hay, Alan J. (author);Gregory, Victoria (author);Douglas, Alan R. (author);Yi, Pu Lin (author)

• Book ID: 111912386
• Publisher: Royal Society
• Year: 2001
• Tongue: English
• Weight: 286 KB
• Volume: 356
• Category: Article
• ISSN: 0080-4622
• DOI: 10.1098/rstb.2001.0999

✦ Synopsis

The evolution of influenza viruses results in (i) recurrent annual epidemics of disease that are caused by progressive antigenic drift of influenza A and B viruses due to the mutability of the RNA genome and (ii) infrequent but severe pandemics caused by the emergence of novel influenza A subtypes to which the population has little immunity. The latter characteristic is a consequence of the wide antigenic diversity and peculiar host range of influenza A viruses and the ability of their segmented RNA genomes to undergo frequent genetic reassortment (recombination) during mixed infections. Contrasting features of the evolution of recently circulating influenza AH1N1, AH3N2 and B viruses include the rapid drift of AH3N2 viruses as a single lineage, the slow replacement of successive antigenic variants of AH1N1 viruses and the co–circulation over some 25 years of antigenically and genetically distinct lineages of influenza B viruses. Constant monitoring of changes in the circulating viruses is important for maintaining the efficacy of influenza vaccines in combating disease.