Factors associating with the spread of RSV in infants

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K24250
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0908:Society medicine, nursing, and related fields
• Research Institution: Nagasaki University (2021); Tohoku University (2019-2020)
• Principal Investigator: OTOMARU Hirono 長崎大学, 熱帯医学研究所, 助教 (00849416)
• Project Period (FY): 2019-08-30 – 2022-03-31
• Keywords: RSV / 世帯内感染 / 感染伝播

Outline of Final Research Achievements

Respiratory Syncytial Virus (RSV) is the causative virus of respiratory infections, particularly severe in infants. Although the importance of intra-household transmission has been reported, the detailed transmission dynamics remain unclear. This study aimed to examine the factors that associate with the spread of RSV to infants.
Based on the analysis of data collected in households in the Philippines in which a family member was infected with RSV, we showed that secondary infection occurred within a short period after the family member became infected. The risk of secondary infections in the household was significantly higher for children under five. Still, there was no association between this risk and the onset of cough in the index case.

Free Research Field

感染症疫学

Academic Significance and Societal Importance of the Research Achievements

RSVは世界的に流行が見られる下気道感染症の原因ウイルスである。本研究では、RSVの感染伝播に関連する疫学的な解析により、乳児を含む5歳未満児で特に二次感染率が高いことを示した。感染時点およびウイルス排出量の変化を推定する解析の結果、家族が最初に感染したのちのごく早い時期から二次感染が起きることが明らかになった。これらのことから、家族が感染した場合は速やかに感染予防策を実施する必要があることがわかった。また、症状が明らかではない感染者からも感染伝播が起きることから、症状に関わらないデータ収集の必要性が示された。大規模なRSV感染拡大を予防する対策の導入に必要となる知見を得ることができた。