Influenza vaccine strain selection and recent studies on the global migration of seasonal influenza viruses

Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, United Kingdom
Vaccine (Impact Factor: 3.77). 09/2008; DOI: 10.1016/j.vaccine.2008.07.078
Source: PubMed

ABSTRACT Annual influenza epidemics in humans affect 5–15% of the population, causing an estimated half million deaths worldwide per year [Stohr K. Influenza—WHO cares. Lancet Infectious Diseases 2002;2(9):517]. The virus can infect this proportion of people year after year because the virus has an extensive capacity to evolve and thus evade the immune response. For example, since the influenza A(H3N2) subtype entered the human population in 1968 the A(H3N2) component of the influenza vaccine has had to be updated almost 30 times to track the evolution of the viruses and remain effective. The World Health Organization Global Influenza Surveillance Network (WHO GISN) tracks and analyzes the evolution and epidemiology of influenza viruses for the primary purpose of vaccine strain selection and to improve the strain selection process through studies aimed at better understanding virus evolution and epidemiology. Here we give an overview of the strain selection process and outline recent investigations into the global migration of seasonal influenza viruses.

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Available from: Masato Tashiro, Aug 12, 2015
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    • "In human influenza viruses, the vaccine strain for target season t is identified at the end of season t − 1 (pre-target season) from the epidemic viruses isolated by then (Treanor, 2004; Russell et al., 2008a). To identify, retrospectively, the most effective vaccine strain for each target season of 2001.0 ≤ t ≤ 2014.5, the average antigenic distance was computed between each of the strains isolated in seasons 1992.0 to t − 1 and the epidemic viruses sampled in season t. "
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    06/2015; 4. DOI:10.1016/j.mgene.2015.03.003
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    • "e grouped under B / Yam and B / Vic . Lineages . Others that were isolated before 1983 were not included in this classification . Numbers at each node of the tree show bootstrap percentages obtained after 1 , 000 replicates . been identified " East and Southeast Asian circulation network " as a leading migration route to Europe and North America [ Russell et al . , 2008 ] ."
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    Journal of Medical Virology 06/2014; 86(6). DOI:10.1002/jmv.23819 · 2.22 Impact Factor
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    • "Preventive measures against circulating H5N1 strains have received a lot of interest and effort globally to prevent another pandemic outbreak [11]. To overcome such limitations without any reduction in the vaccine efficacy and to completely realize the potential of vaccines worldwide, the concept of universal vaccines based on representative hemagglutinin mix has recently been proposed [12]. With an understanding in the distribution pattern of HA neutralizing epitopes, a trivalent H5 vaccine has been developed and proved to provide universal protection against multiple clades of H5 influenza viruses. "
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    03/2013; 2013:360675. DOI:10.1155/2013/360675
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