Outbreak Investigation
Strain of multidrug-resistant Salmonella Typhimurium outbreak in a southern county, Taiwan, January–June 2023
DOI: 10.6524/TEB.202411_40(22).0002Pei-Yuan Wu1*, Chia-ping Su2,3, Ying-Shu Liao1, Chien-Shun Chiou1
2024 Vol.40 NO.22
Correspondence Author： Pei-Yuan Wu1*
- 1Center for Research, Diagnostics and Vaccine Development, Centers for Disease Control,
- Ministry of Health and Welfare, Taiwan
- 2Division of infectious disease, Department of medicine, New Taipei Municipal TuCheng Hospital
- 3National Tsing Hua University School of Post-Baccalaureate Medicine
Abstract：
The Taiwan Centers for Disease Control detected a novel multidrug-resistant strain of Salmonella Typhimurium (S. Typhimurium) in southern Taiwan in 2023, predominantly pulsed-field gel electrophoresis (PFGE) genotype STX.1725. We conducted an epidemiological investigation to understand the severity of infections caused by this strain and to identify possible sources of infection.
Cases were under the age of 18 years diagnosed with S. Typhimurium STX.1725 reported by Hospital B in County A during January to June 2023. Two case-control studies were conducted. The first study compared cases to a randomly sampled population under the age of five years nationwide as controls. The second was a matched pair case-control study. The controls were selected from children admitted to Hospital B for non-gastrointestinal illnesses, matched for age and admission date with the cases.
Of the 38 cases identified, predominant symptoms were diarrhea (97%) and fever (92%). One had invasive infection, but no severe cases or fatalities occurred, and severity was similar to typical Salmonella infections. Eating out, takeaway foods, and unpackaged eggs showed higher odds ratios but lacked statistical significance.
Identifying a common infection source was challenging due to lack of evidence. We recommended continued monitoring of this strain, and collaboration with stakeholders for future investigations.
