Prevalence and molecular epidemiology of Legionnaires' disease

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K18922
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 58020:Hygiene and public health-related: including laboratory approach
• Research Institution: Toyama Institute of Health
• Principal Investigator: Kanatani Jun-ichi 富山県衛生研究所, 細菌部, 主任研究員 (80463131)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: レジオネラ / ゲノム分子疫学解析

Outline of Final Research Achievements

The objective of this study is to diagnose potential Legionnaires' disease patients through proactive sputum culture testing and to elucidate the sources of infection. Culture testing was conducted on respiratory specimens from 189 cases, resulting in the isolation of Legionella pneumophila serogroup 2 (Lp2) from two specimens. Subsequent phylogenetic analysis of the whole genome sequences of the Lp2 isolates including those from various environmental sources revealed that clinical isolates were closely related to the isolates derived from puddles. Therefore, it was suggested that patients infected with these isolates might have been infected in locations other than bathing facilities.

Free Research Field

細菌学

Academic Significance and Societal Importance of the Research Achievements

従来の尿中抗原検査試薬はLegionella pneumophila血清群1（Lp1）以外の菌種・血清群に対する感度は著しく低いため、Lp1以外のレジオネラ属菌に感染している患者は把握されていない。したがって、現在まで、国内において、Lp1以外を原因菌とする潜在的なレジオネラ症患者の実態はよくわかっていない。本研究により、従来の尿中抗原検査では診断できない、Lp1以外を原因菌とする潜在的なレジオネラ症患者の存在が明らかとなった。