Analytic epidemiology about protection against influenza among infants under 6 months of age

2015 Fiscal Year Final Research Report

• Project/Area Number: 25293152
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Hygiene and public health
• Research Institution: Osaka City University
• Principal Investigator: OHFUJI Satoko 大阪市立大学, 大学院医学研究科, 准教授 (70433290)
• Co-Investigator(Kenkyū-buntansha): FUKUSHIMA Wakaba 大阪市立大学, 大学院医学研究科, 教授 (70420734) ; KONDO Kyoko 大阪市立大学, 医学部・附属病院運営本部, 技術職員 (80420727) ; MAEDA Akiko 大阪市立大学, 大学院医学研究科, 研究員 (40250279)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 感染症 / インフルエンザ / 乳児 / 疫学 / ワクチン有効性

Outline of Final Research Achievements

To examine the effectiveness of maternal influenza vaccination on preventing influenza in infants under 6 months of age, we conducted a cohort study among 4,068 infants born before 2013/14 influenza season in Osaka. During 2013/14 season, a total of 85 infants (2%) were diagnosed with influenza and 19 infants (0.5%) were hospitalized with influenza. Maternal influenza vaccination (especially prenatal vaccination) revealed to have a decreasing effect on infants' influenza. Vaccine effectiveness of prenatal vaccination was 60% (95% confidence interval: 13%-82%), whereas that of postpartum vaccination was 48% (-41-81%). Although maternal influenza vaccination was also associated with decreasing infants' influenza-related hospitalization, vaccine effectiveness (70%) could not reach to the statistically significance due to limited number of hospitalized cases.
Present findings indicated that pregnant women should receive influenza vaccination in order to protect their infants.

Free Research Field

疫学・公衆衛生学