Dissemination of antimicrobial-resistant bacteria from hospital sewage to natural environments

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K19403
• 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: Hokkaido University
• Principal Investigator: Okubo Torahiko 北海道大学, 保健科学研究院, 講師 (90762196)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 薬剤耐性菌 / 微生物間相互作用 / 繊毛虫 / ワンヘルス

Outline of Final Research Achievements

In this study, extended-spectrum β-lactamase-producing E. coli (n=44) were isolated from manhole sewage. Although there was no significant difference in the frequency of resistance between general facility sewage and hospital sewage, the hospital sewage-derived strain was resistant to fluoroquinolones in addition to β-lactam resistance. These results indicate that sewage is an important pathway for the spread of drug-resistant bacteria into the environment, and that hospital sewage in particular contains drug-resistant bacteria that have become highly resistant. In addition, Anteglaucoma harbinensis and nine other strains of ciliates were isolated from sewage. Anteglaucoma showed a unique characterization of Legionella susceptibility, which provided a secondary ciliate useful as a tool in the search for virulence factors of Legionella.

Free Research Field

微生物間相互作用

Academic Significance and Societal Importance of the Research Achievements

本研究では汚水から薬剤耐性菌を検出できたことに加え、病院汚水と一般施設汚水との間で薬剤耐性菌の質的・量的な差を比較することができた。このことから、病院汚水には単に薬剤耐性菌が含まれるだけでなく、より耐性化が進んだ高度耐性菌が含まれることを明らかにした。薬剤耐性菌の環境中への拡散は世界的な懸念事項となっているため、その対策が求められている。本研究の成果は病院汚水に対して耐性菌拡散防止対策が必要なことを示す具体的なエビデンスを示しており、臨床と環境をつなぐワンヘルスアプローチに関わる知見を提供するものである。