Influenza Evolution and H3N2 Vaccine Effectiveness, with Application to the 2014/2015 Season
Xi Li, Michael W. Deem

H3N2 Influenza A is a serious disease which can lead to hospitalization and which causes significant morbidity and mortality. Vaccines against the seasonal influenza disease are of variable effectiveness, for example being fairly low in the 2014/2015 Northern hemisphere season. In this paper, we discuss use of the pepitope method to predict the dominant influenza strain and the expected vaccine effectiveness in the coming flu season. We illustrate how the current A/Texas/50/2012 vaccine is not expected to be protective against the A/California/02/2014 strain that has emerged in the population, consistent with recent observations. In addition, we used multidimensional scaling to cluster the A/H3N2 hemagglutinin from GenBank to find that there is a transition underway from the A/California/02/2014 to the A/New Mexico/11/2014 strain, suggesting the latter may be an appropriate vaccine component for next season.