It is uncertain if there are any short-term dynamic changes in neutralising antibodies against EV71 and EV71-IgM following inactivated EV71 vaccine injection. This was a randomised, open-label trial that was filed at ClinicalTrials.gov (NCT03278132). In all, 120 healthy babies aged 6–35 months were randomised 1:1:1 to produce a second blood sample 10 days, 20 days, or 30 days following the first immunisation dose. A fast immune response against EV71 was detected 10 days following the initial EV71 vaccination dose, with antibody titers 1:8 in 89.19 percent of individuals on day 10, 80.65 percent on day 20, 66.67 percent on day 30, and 100 percent on day 60, according to the protocol. The percentages of subjects that tested positive for EV71-IgM on day 0 and day 60 were 1.71 percent (2 out of 117) and 82.86 percent (87 out of 105), respectively, according to an ELISA.

To further prevent EV71-associated illness outbreaks, the EV71 vaccine might be utilised for contingency immunisation. Using the EV71-IgM test for quick EV71 infection identification following EV71 vaccination delivery should be done with caution.

Reference: https://www.tandfonline.com/doi/full/10.1080/21645515.2020.1711678