Why were retail chicken meat still contaminated with cephalosporin-resistant Salmonella? Research to elucidate the cause and to reduce the contamination

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K19428
• 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: Fukuoka Institute of Health and Environmental Sciences
• Principal Investigator: Shigemura Hiroaki 福岡県保健環境研究所, その他部局等, 研究員 (50761540)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: サルモネラ / 安定同位体比 / 薬剤耐性 / 鶏肉 / 保有率

Outline of Final Research Achievements

Retail chicken meat were still contaminated with extended-spectrum cephalosporin (ESC)-resistant Salmonella, despite the voluntary withdrawal of ceftiofur in Japanese poultry industry. It was expected that the cause of the contamination might be in relation with the specific genes on Salmonella plasmid. However, it could not be clarified. Also, it was examined whether stable isotope ratio analysis could be used as a method to estimate the producing area of chicken meat contaminated with ESC-resistant Salmonella. The method might be available for chicken meat samples showing characteristic distributions in two dimensional plot of principal component analysis. In addition, this study revealed that some humans without clinical symptoms were infected with ESC-resistant Salmonella. Several serovars of the human ESC-resistant Salmonella were the same serovars isolated from chicken meat, suggesting the possibility of transmission from chicken meat to human.

Free Research Field

公衆衛生、細菌

Academic Significance and Societal Importance of the Research Achievements

市販鶏肉を汚染したESC耐性サルモネラのblaTEM保持プラスミドにセフチオフル使用自粛前後で大きな違いがないことを本研究で明らかにした。さらに、無症状のヒトのサルモネラ保菌状況およびサルモネラのESC耐性状況を明らかにすることができた。これらはESC耐性サルモネラの拡散制御のための基礎的な知見となり、今後の研究への発展および公衆衛生上の対策等に寄与することが期待される。