2026/03/01 by Masatomo Morita, Kenichi Lee, Akio Sugiyama +4 · 1 voice
Agricultural and Biological Sciences · Immunology and Microbiology · Medicine · #Aquaculture disease management and microbiota #Infectious Encephalopathies and Encephalitis #Salmonella and Campylobacter epidemiology
paper · doi:10.1099/acmi.0.001121.v4
openalex publication_date 2026/03/01 · openalex created_date 2026/03/14 · openalex updated_date 2026/06/11
Introduction. Typhoid fever, caused by Salmonella enterica serovar Typhi, is a systemic infection. Approximately 40 cases occur annually in Japan, most of which are imported. In August 2023, a researcher engaged in phage typing of S . Typhi was diagnosed with typhoid fever. Case Presentation. A 48-year-old man presented with high fever, diarrhoea, malaise and loss of appetite. Initial findings, including liver dysfunction and severe inflammation, led to a suspected diagnosis of autoimmune disease. However, blood cultures identified S . Typhi, confirming typhoid fever. Comparative genomic analysis demonstrated clonality between the strain handled in the laboratory and the patient isolates, indicating a laboratory-acquired infection. Conclusion. This case underscores the need for ongoing vigilance regarding the risk of laboratory-acquired infections and highlights the value of whole-genome sequencing for tracking. It would be also emphasized that this is the first reported case in Japan linked to phage typing, a conventional typing method for S . Typhi. This raises the urgency of transitioning from phage typing to genotyping and recommends mandatory typhoid vaccination for laboratory personnel working with S . Typhi to minimize infection risk.