Table 1. Antibody response of vaccinated horses boosted with the updated EI vaccine.
| Indicator viruses | Virus profiles | GM VN | |
|---|---|---|---|
| Pre V | Post V | ||
| A/equine/La Plata/1993 | Removed from the updated vaccine | 143.0 | 188.7 |
| A/equine/Ibaraki/1/2007 | Contained in the original and updated vaccine, Florida sub-lineage Clade (Fc) 1 | 205.1 | 337.8 |
| A/equine/Yokohama/aq13/2010 | Newly added to the vaccine, Fc 2 | 199.5 | 410.1 |
| A/equine/Ayrshire/1/2013 | Fc2 with I179V substitution | 111.4 | 173.6 |
| A/equine/Carlow/2011 | Fc2 with A144V substitution | 49.9a) | 114.6 |
| A/equine/Devon/1/2011 | Fc2 with A144V substitution | 57.3a) | 108.4a) |
GM VN, geometric mean virus neutralization titre (n=25); Pre V, on day of vaccination; Post V, one month post vaccination. a) Statistical significance between the Pre GM VN titer against A/equine/Ibaraki/1/2007 (base-line, 205.1) and the Pre and Post GM VN titers against the four Fc2 viruses (P<0.05, Friedman’s test with Dunn’s multiple comparison tests).