TABLE.
Seroprotection (PRNT50 titer ≥10) at 1 month after a 2-dose primary series of inactivated Vero cell culture–derived Japanese encephalitis vaccine (JE-VC) administered according to the dose and schedule approved by the Food and Drug Administration (FDA)*
| 0.25 mL dose | 0.5 mL dose | ||||
|---|---|---|---|---|---|
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|
|
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| Study location | Age group | No. | (%) | No. | (%) |
| Philippines | 2 mos–17 yrs | 147/148 | (99)† | 237/237 | (100) |
| India | 1–2 yrs | 22/23 | (96) | — | —§ |
| United States/Europe/Australia | 2 mos–17 yrs | 5/5 | (100) | 46/46 | (100) |
Abbreviation: PRNT50 = 50% plaque reduction neutralization test.
For children aged 2 months–2 years, two 0.25 mL doses administered 28 days apart; for children aged 3–17 years, two 0.5 mL doses administered 28 days apart.
Of an additional 98 children aged 3–11 years who received two 0.25 mL doses, 94 (96%) were seroprotected at 1 month after the second dose.
Of 21 children aged 1–2 years who received two 0.5 mL doses, 20 (95%) were seroprotected at 1 month after the second dose; the FDA-approved dose for children aged 1–2 years is 0.25 mL.