2019 Fiscal Year Final Research Report
Infant Risk and Estimated Incidence of Pertussis Infection in Vietnam
| Project/Area Number |
17K15829
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| Research Category |
Grant-in-Aid for Young Scientists (B)
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| Allocation Type | Multi-year Fund |
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| Research Field |
Epidemiology and preventive medicine
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| Research Institution | Nagasaki University |
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Principal Investigator |
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| Project Period (FY) |
2017-04-01 – 2020-03-31
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| Keywords | 百日咳 / ワクチン / seroprevalence / 出生コホート |
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| Outline of Final Research Achievements |
We enrolled 1570 newborn babies in Nha Trang, Vietnam and tested their cord blood for anti-Bordetella pertussis toxin IgG antibody. The geometric mean titer was 9.98IU/ml. The antibody was lower than 10IU/ml as under the protective level in 51.4% of the neonates.
We enrolled people aged 0-5 (n=100), 6-15 (n=107), 16-25 (n=105), 26-35 (n=94), 36-55 (n=104) in the community of Nha Trang and tested their blood for anti-pertussis toxin antibody.The geometric mean titer was 10.20IU/ml among those aged 3 or more, assuming they had less effect by vaccination. The antibody titer was higher among children and young adults (age 3-25). Pertussis infection was estimated to occur in children and young adults at a higher rate.
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| Free Research Field |
小児感染症学
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| Academic Significance and Societal Importance of the Research Achievements |
ベトナムでは1985年に乳児DPTワクチンが導入され百日咳発生率は低下したが、2010年代にも百日咳症例が報告されている。その多くが乳児例であり、軽症例のほとんどは見過ごされてきている。より効果的な百日咳予防策を講じるため、最も脆弱なワクチン接種前乳児の抗体保有率および年齢層別の百日咳発生率を把握する必要があった。本研究により、ベトナムの一都市において出生した新生児の約半数が感染防御閾値未満の移行抗体しか持たず、小児・若年成人を中心に百日咳感染が起こっていることが明らかになった。妊婦または小児・若年成人へのブースターワクチン接種導入の検討が必要である。
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