Persistence of Wild-Type Japanese Encephalitis Virus Strains Cross-Neutralization 5 Years After JE-CV Immunization.
J Infect Dis
; 215(2): 221-227, 2017 Jan 15.
Article
em En
| MEDLINE
| ID: mdl-27815383
ABSTRACT
BACKGROUND:
The live-attenuated Japanese encephalitis (JE) vaccine (JE-CV; IMOJEV) induces a protective response in children. A shift in circulating JE virus strains suggests that a genotype shift phenomenon may occur throughout Southeast Asia. We assessed the neutralization of wild-type (WT) JE virus isolates at distal time points after vaccination.METHODS:
We analyzed serum samples from a subset of 47 children who had received a JE-CV booster after an inactivated JE vaccine primary immunization. We measured antibody titers (50% plaque reduction neutralization test) using a panel of WT JE strains at baseline, then after the booster at 28 days and 6 months in all subjects present at the time points and in a subset at year 5. Three additional recent isolates were tested at year 5.RESULTS:
Of 47 subjects, 43 (91.5%) subjects had JE neutralizing antibody titers ≥10 (reciprocal serum dilution) against the homologous strain before JE-CV boost; all were seroprotected up to year 5 after the JE-CV boost. Baseline WT seroprotection ranged between 78.7% and 87.2%; all subjects were seroprotected against the 4 WT strains at 28 days and 6 months; year 5 seroprotection ranged between 95.7% and 97.9%. Similar rates of protection against 3 additional WT isolates were observed at year 5.CONCLUSIONS:
The long-term immune responses induced after a JE-CV booster dose in toddlers were able to neutralize WT viruses from various genotypes circulating in Southeast Asia and India. CLINICAL TRIALS REGISTRATION NCT00621764.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Reações Cruzadas
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Vacinas contra Encefalite Japonesa
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Vírus da Encefalite Japonesa (Espécie)
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Anticorpos Neutralizantes
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Anticorpos Antivirais
Limite:
Animals
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Child, preschool
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Female
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Humans
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Male
País/Região como assunto:
Asia
Idioma:
En
Revista:
J Infect Dis
Ano de publicação:
2017
Tipo de documento:
Article