Epidemiological and Pathogenic Features of Legionella pneumophila Serogroup 1 Clinical and Environmental Isolates in Japan

2015 Fiscal Year Final Research Report

• Project/Area Number: 24510038
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Environmental impact assessment/Environmental policy
• Research Institution: Toho University
• Principal Investigator: OHNO Akira 東邦大学, 医学部, 講師 (40223903)
• Co-Investigator(Kenkyū-buntansha): KATO Naoyuki 東邦大学, 医学部, 准教授 (50104154)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: Legionella pneumophila / Serogroup1 / Subgroup / Sequence type / 臨床分離株 / 環境分離株 / 64kb pathogenic island / 塩素耐性

Outline of Final Research Achievements

This study demonstrated that the characteristics of Legionella pneumophila serogroup1(SG1), the major causative agent of Legionnaires' disease, was distinctly different between clinical isolates and environmental isolates despite of the same serogroup, and the environmental isolates carried frequently the strain-specific elements(the Lvh typeIVA secretion system and the 65kb pathogenic island(PI)) not shared by a number of clinical isolates. Further we found that the 65kb PI had a role for chlorine tolerance. Finally, we concluded that the fact that the Benidorm type subgroups, most common in clinical isolates, were not found in cooling tower isolates but relatively predominant in hot spring isolates might relate to that legionella infection occurs mostly at spa facilities.

Free Research Field

微生物学