20 August 2026
A team led by Chinese CDC researchers uncovered that a severe foodborne outbreak striking 130 kindergarten attendees was caused by a rare serotype, Salmonella Braenderup (ST311), driven by raw egg cross-contamination and persistent local circulation.
In July 2025, public health authorities in Yangjiang City, Guangdong Province, were alerted after multiple children presented with acute gastrointestinal symptoms, shortly following a kindergarten graduation event.
An epidemiological investigation into the 676 ceremony attendees identified 130 probable cases (overall attack rate of 19.2%), predominantly affecting 5-year-old children across two campuses (attack rates of 48.4% and 44.7%).
A case-control study decisively pointed to bakery-produced sandwiches as the outbreak vehicle. Salmonella Braenderup Sequence Type 311 (ST311) was isolated from 34 patient stool samples, leftover sandwich portions, and raw shell eggs sourced from an egg farm in Gaozhou City. Although the sandwiches did not contain eggs as an intentional recipe ingredient, shared preparation tables and unhygienic handling transferred high bacterial loads from bakery pastries containing raw eggs to ready-to-eat sandwich loaves.
Ao H et al. (2026). A Foodborne Disease Outbreak Caused by Salmonella enterica Serovar Braenderup (ST311) - Yangjiang City, Guangdong Province, China, July 2025. China CDC Weekly, 8(30): 948–953
