11.04.2024 - Mikrobiologie

Detection of isolates of Listeria spp. and Listeria monocytogenes using the MALDI-TOF method

In crisis situations it is necessary to quickly identify and eliminate the cause of contamination. The BAV INSTITUT offers comparative analysis of microorganisms using the MALDI-TOF method.

In recent years, food contamination with Listeria monocytogenes has increasingly been the reason for recalls, illnesses or crises.
In such cases, a rapid and reliable identification of the source of contamination ("root cause analysis") is required. This can be a major challenge because Listeria spp. and Listeria monocytogenes are common in our environment and their presence in food companies cannot usually be completely ruled out.

These bacteria can regularly be introduced into the business through raw materials or staff, for example. Many crises caused by Listeria monocytogenes are, however, caused by strains that have permanently colonised the business. These strains are also known as "persistent" Listeria monocytogenes. These Listeria strains often originate from biofilms.

In the past, persistent Listeria monocytogenes strains have been the cause of several serious outbreaks of disease. In order to determine the origin of the bacterial strains and to decide whether they originate from raw materials or from the company's environment, a strain comparison is required.

At BAV INSTITUT, these analyses are carried out using the MALDI-TOF method. This is faster and more cost-effective than molecular biological methods, which are also used for this purpose. The results of the strain comparison analyses with MALDI-TOF are available on the same day after cultural isolation.

Strain comparison tests are also possible for other pathogens such as Salmonella, Bacillus cereus, Staphylococcus aureus, Cronobacter spp.... However, this method can also be successfully used to quickly analyse the cause of contamination with spoilage organisms such as lactic acid bacteria, acetic acid bacteria, pseudomonads or yeasts.

Using this method and other rapid methods such as RT-PCR, our experts can provide fast and reliable support in crisis situations.

If you have any questions, please do not hesitate to contact us.