Fig. 4

Cumulative cases of hand, foot, and mouth disease (HFMD) reported in 350 participants. A total of 350 participants (161 individuals in the vaccine group and 189 in the placebo group), who provided a full series of blood samples (at all the sampling points) within the 2-year study period, were observed during the surveillance period. The cumulative curves for the cases of HFMD induced by enterovirus 71 (EV71), coxsackievirus A16 (CA16), and other enteroviruses were estimated as a percentage among these participants with Kaplan–Meier survival curves during the period from the receipt of the first dose until 24 months thereafter. The inset shows the same data on an enlarged y-axis. Differences in the distributions of cases of HFMD among the individuals who received the placebo and those who received the vaccine were evaluated with a log-rank test. a Cumulative curve for the cases of HFMD induced by EV71. b Cumulative curve for the cases of HFMD induced by CA16. c Cumulative curve for the cases of HFMD induced by other enteroviruses