Table I.
Historical vaccine strains, circulating strains and vaccine effectiveness
| Year | Vaccine | Circulating strain | Dominant strain epitope | P epitope | Vaccine effectiveness | n u | N u | n v | N v | d 1 | d 2 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2004–05 | A/Wyoming/3/2003 (AY531033) | A/Fujian/411/2002 (AFG72823) | B | 0.095 | 9% (Ndifon et al., 2009) | 6 | 40 | 50 | 367 | 2 (Huang, 2008) | 1 (Huang, 2008) |
| 2005–06 | A/New York/55/2004 (AFM71868) | A/Wisconsin/67/2005 (AFH00648) | A | 0.053 | 36% (Skowronski et al., 2007) | 43 | 165 | 6 | 36 | 1 (World Health Organization, 2006a) | 2 (World Health Organization, 2006a) |
| 2006–07 | A/Wisconsin/67/2005 (ACF54576) | A/Hiroshima/52/2005 (ABX79354) | A | 0.105 | 5% (Skowronski et al., 2009) | 130 | 406 | 20 | 66 | 1 (Bulimo et al., 2008) | 2 (Bulimo et al., 2008) |
| 2007 | A/Wisconsin/67/2005 (ACF54576) | A/Wisconsin/67/2005 (AFH00648) | B | 0.048 | 54% (Fielding et al., 2011) | 74 | 234 | 8 | 55 | ||
| 2008–09 | A/Brisbane/10/2007 (ACI26318) | A/Brisbane/10/2007 (AIU46080) | 0 | 51% (Simpson et al., 2015) | 36 | 240 | 4 | 54 | |||
| 2010–11 | A/Perth/16/2009 (AHX37629) | A/Victoria/208/2009 (AIU46085) | A | 0.053 | 39% (World Health Organization, 2011; Treanor et al., 2012) | 100 | 991 | 35 | 569 | 0 (European Center for Disease Prevention and Control, 2011) | 1.4 (European Center for Disease Prevention and Control, 2011) |
| 2011–12 | A/Perth/16/2009 (AHX37629) | A/Victoria/361/2011 (AIU46088) | C | 0.111 | 23% (World Health Organization, 2012; Castilla et al., 2013) | 335 | 616 | 47 | 112 | 1 (Martin et al., 2015) | 2.8 (Martin et al., 2015) |
| 2012–13 | A/Victoria/361/2011 (AGB08328) | A/Victoria/361/2011 (AIU46088) | B | 0.095 | 35% (Kissling et al., 2014) | 288 | 1257 | 15 | 100 | 5 (World Health Organization, 2013) | 4 (World Health Organization, 2013) |
| 2013–14 | A/Victoria/361/2011 (AGL07159) | A/Texas/50/2012 (AIE52525) | B | 0.190 | 12% (Castilla et al., 2014) | 145 | 476 | 16 | 60 | 5 (World Health Organization, 2013) | 4 (World Health Organization, 2013) |
| 2014–15 | A/Texas/50/2012 (AIE52525) | A/California/02/2014 (AIE09741) | B | 0.191 | 14% (Flannery et al., 2015) | 135 | 342 | 100 | 293 | 4 (World Health Organization, 2014b) | 5.6 (World Health Organization, 2014b) |
H3N2 influenza vaccine effectiveness in humans and corresponding pepitope antigenic distances for the 2004–15 seasons. The vaccine and circulating strains are shown for each of the years since 2004 in which H3N2 virus has been the predominant influenza virus and for which vaccine effectiveness data are available. Vaccine effectiveness values are taken from the literature. Here Nu is the total number of unvaccinated subjects, Nv is the total number of vaccinated subjects, nu is the number of H3N2 influenza cases among the unvaccinated subjects and nv is the number of H3N2 influenza cases among the vaccinated subjects. Also shown are the distances derived from ferret HI data by the two common measures (Gupta et al., 2006).