A multi-city outbreak of Salmonella Enteritidis infections linked to bakery products, Republic of Korea
10.24171/j.phrp.2025.0467
- Author:
Da Seul KIM
1
;
Soon-Young SEO
;
Dong Hwi KIM
;
Yeon Hee WOO
;
Deborah LEE
;
Se Jeong YANG
;
Junyoung KIM
;
Eunkyung SHIN
;
Byungsun JUNG
;
Eunmi LEE
;
Min Jung LEE
;
Young-Joon PARK
Author Information
1. Division of Infectious Disease Control, Korea Disease Control and Prevention Agency, Cheongju, Republic of Korea
- Publication Type:Original Article
- From:
Osong Public Health and Research Perspectives
2026;17(1):61-71
- CountryRepublic of Korea
- Language:English
-
Abstract:
Objectives:In May 2025, clusters of salmonellosis were identified in 7 cities in the Republic of Korea, all associated with consumption of identical bakery products. This investigation aimed to characterize the outbreak, identify potential contributing factors, and inform strategies for preventing similar multi-facility foodborne outbreaks.
Methods:A case series study was conducted among individuals who consumed Manufacturer H’s Product I and Product II on May 15–16, 2025 at 7 facilities (n = 1,235). Clinical specimens from symptomatic individuals, retained food samples, and environmental samples were collected and tested. Food-exposure histories were assessed, and active case finding was implemented across all supplied facilities. Traceback investigations were conducted at the manufacturer, distributor, and egg farms. Human and food isolates underwent pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS).
Results:A total of 323 cases met the outbreak case definition (attack rate, 26.2%), of which 48 were laboratory-confirmed. Salmonella Enteritidis was isolated from both clinical specimens and retained bakery products. PFGE patterns were indistinguishable between human and food isolates, and WGS demonstrated high genetic relatedness. These findings confirmed a common-source outbreak linked to the implicated bakery products.
Conclusion:This outbreak underscores the value of integrating epidemiological investigation, active case finding, and molecular typing to identify common food vehicles in outbreaks involving widely distributed manufactured foods. Coordinated collaboration between public health and food safety authorities is essential for the effective detection, response, and prevention of multi-facility foodborne outbreaks.
