Here's how to prevent a Listeria outbreak

Eating food containing the bacteria Listeria monocytogenes can lead to a food infection with serious consequences. Therefore, if you work with food products, you want to do everything possible to prevent an infection. How do you do this? That's what Aldo Evers, Technical Director Microbiology at Normec Foodcare, tells us.

Why do you need to be well informed about Listeria?

The Belgian FAVV reported 38 Listeria-related recalls in 2024, the Dutch NVWA reported 1 listeria-related recall. Aldo explains: "That means that several times products have been in stores where consumers could become (seriously) ill within the shelf life. That alone should be a reason to have Listeria control high on the agenda within your food company."

Listeria has become a business risk in addition to a public health risk. Aldo adds: "Think of high costs due to recalls, but also liability after illness or death of consumers as a result of eating contaminated food. It is therefore very important to understand within the company where Listeria comes from. You also need to understand the laws and regulations and how the Dutch Food and Consumer Product Safety Authority (NVWA) looks at this. And how to apply modelling and challenge tests to make predictions about Listeria monocytogenes and the risks to your business."

For which companies is Listeria control important?

"Control of Listeria is in fact important for any company than works with food products. But extra attention for Listeria is necessary in companies that produce or trade ready-to-eat products and/or products that fall into category 1.1, 1.2 or 1.3 of Regulation (EC) No. 2073/2005. Please note that this Regulation has been amended as of January 1, 2025 and the limit values are now looked at more strictly," Aldo explained. The Regulation lists the following products under the listed paragraphs:

1. Ready-to-eat infant formula and ready-to-eat foods for medical use
2. Ready-to-eat foods that may serve as breeding grounds for L. monocytogenes
3. Ready-to-eat foods that cannot serve as breeding grounds for L. monocytogenes

What knowledge is necessary for Listeria management?

To prevent infections and outgrowth of Listeria monocytogenes within your company, you need to be well informed and know the right steps to take. Aldo explains, "You need to have knowledge of existing laws and regulations and how to read and interpret them. It is also important to know how to conduct a Listeria study and to understand the role of models and challenge tests, the use of data, different analyses and food sampling. Modern DNA techniques can also be used to identify where Listeria may have come from. And if you are aware of all this, it is also good to know what the NVWA's view is regarding Listeria monocytogenes." So for Listeria control within your company, a lot of knowledge and experience is needed. Aldo adds: "Because we know how wrong it can go and how big the consequences are, we think it is important to provide those responsible in the food sector with the right knowledge and practical experience. We realize this during the two-day Listeria Course of Wageningen University & Research, in cooperation with Normec Foodcare."

How do you know what actions are needed within your company?

"Every company is different and every situation requires a different method of control. By learning various practical examples and solutions and actually getting to work with your own business processes, you will increasingly understand what actions are needed within your company. During the course, speakers from the food sector share their practical experiences. In this way they provide insight into how various Listeria issues are dealt with within the company. The knowledge gained is then put into practice during a practical workshop. Afterwards, you will be able to determine for yourself what the risky products and processes within your company are and how to make and implement a management plan for them," Aldo concludes.