Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1999-9-15
pubmed:abstractText
Placebo-controlled field efficacy trials of new Japanese encephalitis (JE) vaccines may be impractical. Therefore, an animal model to evaluate efficacy of candidate JE vaccines is sought. Previous work has shown that exposure of monkeys to JE virus (JEV) via the intranasal route results in encephalitis. Here we report the further development of this model and the availability of titered virus stocks to assess the protective efficacy of JE vaccines. To determine the effective dose of our JE challenge virus, dilutions of a stock JEV (KE-93 isolate) were inoculated into four groups of three rhesus monkeys. A dose-dependent response was observed and the 50% effective dose (ED50) was determined to be 6.0 x 10(7) plaque forming units (pfu). Among animals that developed encephalitis, clinical signs occurred 9-14 days postinoculation. Infection with JEV was confirmed by detection of JEV in nervous tissues and IgM to JEV in the cerebrospinal fluid. Viremia with JEV was also detected intermittently throughout infection. Validation of the model was performed using a known effective JE vaccine and saline control. One ED90 of virus (2.0 x 10(9) pfu) was used as a challenge dose. Four of four animals that received saline control developed encephalitis while one of four monkeys administered the JE vaccine did so. This study demonstrates that the virus strain, route of inoculation, dose, and the outcome measure (encephalitis) are suitable for assessment of protective efficacy of candidate JE vaccines.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0002-9637
pubmed:author
pubmed:issnType
Print
pubmed:volume
60
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
329-37
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10466957-Administration, Intranasal, pubmed-meshheading:10466957-Animals, pubmed-meshheading:10466957-Animals, Suckling, pubmed-meshheading:10466957-Antibodies, Viral, pubmed-meshheading:10466957-DNA, Viral, pubmed-meshheading:10466957-DNA Primers, pubmed-meshheading:10466957-Disease Models, Animal, pubmed-meshheading:10466957-Electrophoresis, Agar Gel, pubmed-meshheading:10466957-Encephalitis, Japanese, pubmed-meshheading:10466957-Encephalitis Virus, Japanese, pubmed-meshheading:10466957-Enzyme-Linked Immunosorbent Assay, pubmed-meshheading:10466957-Female, pubmed-meshheading:10466957-Hemagglutination Inhibition Tests, pubmed-meshheading:10466957-Immunization, pubmed-meshheading:10466957-Macaca mulatta, pubmed-meshheading:10466957-Male, pubmed-meshheading:10466957-Mice, pubmed-meshheading:10466957-Neutralization Tests, pubmed-meshheading:10466957-RNA, Viral, pubmed-meshheading:10466957-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:10466957-Viral Vaccines, pubmed-meshheading:10466957-Viremia
pubmed:year
1999
pubmed:articleTitle
An intranasal challenge model for testing Japanese encephalitis vaccines in rhesus monkeys.
pubmed:affiliation
Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't