2016 Fiscal Year Final Research Report
Evaluation of herd immunity using the NA titer against the circulating rubella virus strains.
Project/Area Number |
26860453
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Research Category |
Grant-in-Aid for Young Scientists (B)
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Allocation Type | Multi-year Fund |
Research Field |
Hygiene and public health
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Research Institution | Osaka Prefectural Institute of Public Health |
Principal Investigator |
KANBAYASHI DAIKI 大阪府立公衆衛生研究所, 感染症部, 研究員 (50622560)
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Project Period (FY) |
2014-04-01 – 2017-03-31
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Keywords | 風疹 / 風疹ウイルス / HI抗体 / IgG抗体 / 中和抗体 / 液性免疫 / 集団免疫 / 抗原性決定部位 |
Outline of Final Research Achievements |
The latest rubella outbreak peaked in 2013 and was notable in that 14,344 rubella and 45 congenital rubella syndrome (CRS) cases were reported although the populational immunity represented by hemmaglutination inhibition (HI) titer was above the protective threshold. The genotype 2B rubella virus (RV) strains were responsible for the outbreak. We established a high throughput assay to measure the neutralization antibody(NA) titer and assessed the NA prevalence rate (n=101) against clinical isolates using human sera. Individuals with protective IgG titer represented 88.1% of the population. Consistently, 85.2% of the population had protective NA titers against the vaccine strain. In contrast, 50.5% of the population had protective NA titers against genotype 2B strains. The humoral immunity does not exhibit full cross reactivity to circulating strains. Our data suggest the humoral populational immunity has been over-estimated by not measuring antibody titers toward circulating strains.
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Free Research Field |
ウイルス学 免疫学 分子生物学 公衆衛生学
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