This research was done to evaluate the efficacy and immunogenicity of Sinovac Enterovirus 71 vaccine for up to two years.
10,077 participants were randomised to receive EV71 vaccine or placebo in a 1:1 ratio, and followed for 14 months. Extended follow-up was done for 12 months and the primary endpoint pf the study was EV71-associated HFMD.
The EV71 vaccine showed an efficacy of 95.1% against EV71-associated HFMD in the extended follow-up, and showed an overall efficacy of 94.7% for two years. The vaccine induced a high level of neutralising antibodies in the patients, with no serious side effects observed.
Therefore, it shows that the vaccine is able to provide a high protection against EV71-associated HFMD for up to 2 years.