A Large-scale Food Poisoning Outbreak Involving Bánh Mì Sold by a Market Stall, Taoyuan City, 2023

Donald Dah-Shyong Jiang¹, Chia-Ying Liao², Yung-Ping Yang², Su-Man Lee², Hui-Wen Hsueh^2*, Tsui-Mi Huang³, Yi-Lien Liu³

2024 Vol.40 No.17

Correspondence Author： Hui-Wen Hsueh^2*

Abstract：

        On August 2 and 3, 2023, hundreds of people in Taoyuan City began to suffer from diarrhea, vomiting, fever, and other symptoms after eating bánh mì sold by a market stall. Taoyuan Health Bureau launched an investigation and set up a telephone hotline along a Google questionnaire to collect information from patients, including bánh mì consumption, disease onset date and time, symptoms, and medical information. Of the 22 human anal bacterial swabs collected from patients, Salmonella enterica serotype Enteritidis was detected in 12 samples. From the investigation results and laboratory tests, it was determined that Salmonella was the causative agent of this food poisoning outbreak. Salmonella enterica serotype Enteritidis was also detected in all 3 samples of bánh mì, so bánh mì was recognized to be the causative food. Based on the ingredients and process of making bánh mì, it was speculated that the egg-yolk containing mayonnaise used in making bánh mì was contaminated with Salmonella. This outbreak showed that the public should choose merchants with good environmental hygiene when buying ready-to-eat foods such as bánh mì, eat them as soon as possible after purchase, and avoid leaving foods at room temperature for too long to avoid spoilage. Also, products with eggs must be fully cooked before eating.

Keywords：foodborne diseases, Salmonella enterica serotype Enteritidis, bánh mì

 

Investigation of a Clostridium perfringens Outbreak in Two Schools, New Taipei City, 2021

Cha-Shien Yen^1,2, Pei-Chen Chen³, Jih-Hui Lin⁴, Chien-Shun Chiou⁴, Hsiao-Lun Wei⁴, Chia-Ping Su^1*

2024 Vol.40 No.17

Correspondence Author： Chia-Ping Su^1*

Abstract：

       In October 2021, over 100 students and staff from two boarding high schools developed gastroenteritis after dinner from the same caterer. We conducted a retrospective cohort study in one school using questionnaires to determine the possible sources of infection. The results showed that the median incubation period was 12.8 hours (range: 0.8–20 hours), and the most common symptoms were diarrhea (81.9%) and abdominal pain (70.0%). Kung-Pao chicken was significantly associated with illness (RR = 4.2; 95% CI 2.7–6.4). Leftovers and stool samples from 19 case-patients were positive for Clostridium perfringens, with whole genome sequencing revealing the same type of bacterial isolates from leftovers and two students from different schools. The growth of C. perfringens was likely due to improper food preservation. We recommend that, hen choosing a caterer, distance from the school should also be considered, so that cooked food could be stored above 60°C and consumed within 2 hours of preparation. Because only one sample was taken from leftovers from each school, it was difficult to determine the infection source from the dinner, even with positive pathogen findings. Therefore, we recommend that separate samples be taken from each meal during the dinner.

Keywords：Clostridium perfringens, food-poisoning, retrospective cohort study