Seroconversion rates and ED50 values of mice inoculated with EV71 FCP-As from three different manufacturers.

Immunization and NAb detection were carried out in three collaborative labs according to the same SOP. Thirty mice were immunized in each dose group. Results were highly repeatable in the three labs and were combined for statistical analysis. ED50 was calculated using the Spearman-Karber method [34].*There were significant differences in seropositive rates induced by the three vaccines at doses of 12.5 U, 3.1 U and 0.8 U (χ2 = 35.22, 15.51 and 18.86, P