Fatal neonatal infection with enterovirus -risk of coxsackie virus B infection-

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K10054
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Pediatrics
• Research Institution: Osaka Institute of Public Health
• Principal Investigator: Nakata Keiko 地方独立行政法人 大阪健康安全基盤研究所, 微生物部, 主任研究員 (50516747)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 新生児エンテロウイルス感染症 / エンテロウイルス / コクサッキーウイルスＢ群 / 手足口病 / ヘルパンギーナ / 環境水調査 / 不顕性感染 / 家族内感染

Outline of Final Research Achievements

Coxsackie virus group B (CV-Bs) belongs to the genus enterovirus (EV), which usually cases mild or subclinical infection. However, there are reports describing severe neonate cases with CV-Bs infection. Here we evaluated the risk of severe infection with CV-Bs among neonates. EV was detected from 23 of 87 enrolled neonates during the study period. The most frequent EV genotype was CV-B5 (31%).
EV-positive neonates had siblings more likely than EV-negative ones (P< 0.01). Also, episodes of infection were reported more often in families with EV-detected neonates (P=0.02). CV-B5 was not prevalent among children during the study period, suggesting that it resulted in mild or subclinical infection among children and adults, but more likely resulted in symptomatic in neonates of naive immune system. These data clarify the risk of CV-B infections among neonates, which we believe is critical in the low birth era although severe cases were not reported during this study period.

Free Research Field

ウイルス学　小児感染症学　免疫学　公衆衛生学　分子生物学

Academic Significance and Societal Importance of the Research Achievements

EV感染症は手足口病やヘルパンギーナ、また近年では弛緩性麻痺の原因となる可能性が示唆されたEV-D68感染症等が知られているが、CV-B群が注目されることはなかった。しかし、本研究ではCV-B群が免疫系の未熟な新生児に感染し、高率に発症することが明らかとなった。幸い、本研究期間中に重症事例は発生しなかったが、少子高齢化時代において新生児の生命を守るための研究として社会的に重要な成果であると考える。