Identifying bacteria that caused many students in the mountainous areas of Khanh Son to get food poisoning

Previously, Capital Labor Newspaper reported that many students at To Hap Town Primary School (Khanh Son District, Khanh Hoa) had symptoms of suspected food poisoning and had to be treated at Khanh District Medical Center. Son became suspicious because he ate rice rolls and rice balls sold on the streets in front of the gate of To Hap Secondary School.

After receiving the news, the Khanh Son District Food Poisoning Investigation Team recorded that all cases had main clinical symptoms: abdominal pain, frequent loose stools, nausea, vomiting. Total number of patients with food poisoning: 74 people (including: 37 students at To Hap Town Primary School, 15 students at To Hap Secondary School, 22 cases in the community).

Through obtaining initial information from medical staff, the patient’s family and the patient, it was recorded that from 6:00 a.m. to 6:30 a.m. on April 9, the poisoned students had one thing in common: they had eaten rice. Rolls and rice balls are sold by a woman on the street near To Hap Secondary School. The food is pre-processed and put into foam boxes and sold to children for breakfast.

According to information from the patient’s family, the woman selling food above has a Facebook name of Quyen Luong. Immediately after that, the Investigation Team contacted and verified Quyen Luong’s Facebook account as Ms. Bui Thi Luong (born 1990) and information that Ms. Luong sold rice balls and rice rolls to students in front of the High School. To Hap facility on the morning of April 9 is correct.

At 12:15 a.m. on April 9, the investigation team began working at Ms. Bui Thi Luong’s house at the address: Hap Phu residential group, To Hap town, Khanh Son district, Khanh Hoa province (where she lived). Housing rental salary).

According to Ms. Bui Thi Luong’s presentation: Every day, Ms. Luong prepares rice rolls and rice balls at home, then stores them in Styrofoam boxes and sells them near To Hap Middle School. On April 9, Ms. Luong sold out 114 rice balls and 28 rice rolls.

Process of making rice balls (including seaweed, rice, crab sticks, fried eggs, mayonnaise, chili sauce, ketchup): Put the ingredients into a plastic mold, cover the lid to shape, then pour out the seaweed pieces. sign to wrap it up and put it in a box.

Process of making rice rolls (including seaweed, rice, crab sticks, fried eggs, fried sausages, stir-fried carrots, shredded cucumber, sliced ​​pickled radish) and dipping sauce (ketchup, mayonnaise) , chili sauce), put the above ingredients on a piece of seaweed and roll it up, then cut it into pieces and put them in a box.

At the time of the investigation, the Investigation Team noted that at Ms. Luong’s house there were no samples of processed rice balls or rice rolls, but only samples of food ingredients. Therefore, the Investigation Team took 11 samples of food ingredients to serve the processing of rice balls and rice rolls, including: Pickled radish, sausage, seaweed rice balls, seaweed rice rolls, chili sauce, and soy sauce. eggplant, carrot, cucumber, mayonnaise, sesame oil, crab stick.

According to Ms. Luong, she and her husband, Mr. Bui Van Ban, participate in preparing food every day. However, when starting food processing and selling street food from the end of August 2023 until now, Ms. Luong and her husband have never had a health check-up or participated in food safety knowledge training classes. products and proactively learn about food safety through the internet.

All samples of food ingredients used to prepare rice balls, rice rolls, hand samples, and stool samples of healthy people are sent to Nha Trang Pasteur Institute for testing.

In addition, at Ms. Luong’s facility there are some food ingredients used to make rice balls and rice rolls, such as seaweed used to make rice rolls, intact, without Vietnamese labels, which Ms. Luong bought through Facebook. account “Yaky Sushi Nori Kwangcheonkim Seaweed Roll 100 Leaves”, without invoices or documents; 7 bags of intact seaweed and 2 bags of slightly used seaweed, without labels, were used to make rice balls, purchased by Ms. Luong via Facebook account “An Lac Vien”, without invoices or documents. ; along with some vegetable ingredients purchased at the market… To serve the investigation, the Investigation Team sealed all remaining food ingredients at the facility.

Through the results of individual investigations of patients with food poisoning, there is one thing in common: They all ate rice balls and rice rolls sold by Mrs. Bui Thi Luong in front of To Hap Middle School on the morning of April 9; Other than that, there are no other shared meals.

Therefore, it was determined that the meal that caused the food poisoning was breakfast at 6:00 a.m. – 6:30 a.m. on April 9.

According to sample testing results of Nha Trang Pasteur Institute: Samples of rolled seaweed detected Staphylococcus aureus bacteria (3.9,102 CFU/g) and detected the endotoxin-producing strain Staphylococcal enterotoxin.

Ingredients samples: Pickled radish, sausage, seaweed rice balls, chili sauce, ketchup, carrots, cucumber, mayonnaise, sesame oil, crab stick: No bacteria detected.

The results of detecting Staphylococcus aureus bacteria (3.9,102 CFU/g) and detecting the endotoxin-producing strain Staphylococcal enterotoxin on the seaweed roll sample, this result is consistent with the results of the sample of the poisoned patient. The food also tested positive for Staphylococcus aureus bacteria.

2/2 hand samples of food handlers (Ms. Bui Thi Luong and Mr. Bui Van Ban) did not detect bacteria.

Test results of clinical samples (stool and vomit samples) of food poisoning patients on April 9, taken at Khanh Son District Medical Center, showed that 7/9 samples were positive for Staphylococcus aureus bacteria. . Investigation results showed that up to 75.5% of investigated cases had an incubation period of 1 – 6 hours, consistent with the incubation period of Staphylococcus aureus bacteria. Therefore, it can be determined that the cause of food poisoning is caused by microorganisms (Staphylococcus aureus bacteria).

Khanh Hoa Provincial Department of Food Safety and Hygiene also proposed that the Police, Department of Industry and Trade, and Market Management Department coordinate and handle violations of the Facebook account “Seaweed rice rolls Yaky Sushi Nori Kwangcheonkim 100 leaves” and Facebook account “An Lac Vien”, places that sold seaweed rice rolls and seaweed rice balls of unknown origin, without product labels according to regulations to Ms. Bui Thi Luong (company). causing food poisoning).