Subtyping Keyvisual

Facilitating Listeria monocytogenes differentation

A dangerous foodborne pathogen 

Listeria monocytogenes is worldwide a very important foodborne pathogen causing potentially fatal listeriosis, with 2,200 cases reported in the EU in 2015. The US center of disease control (CDC) estimates that L. monocytogenes is the third leading cause of death from foodborne illness, or food poisoning, in the United States. The disease affects especially pregnant women and their newborns, people with weakened immune systems and adults aged 65 or older. The latter group represented about 64% of the confirmed cases with known age in the EU; 20% of the cases in this patient group were fatal.*

* European summary report on trends and sources of zoonoses, zoonotic agents and food-borne outbreaks in 2015, published by EFSA and ECDC in 2016. Data on case numbers for Europe come from the European Surveillance system (TESSy). 

 

To be or not to be – the challenge of differentiating Listeria species

The members of the Listeria monocytogenes group (L. monocytogenes, L. ivanovii, L. innocua, L. welshimeri and L. seeligeri) show only slight differences on genetic and proteomic levels. Until recently, there were no rapid solutions for the identification of L. monocytogenes.

Not for use in clinical diagnostic procedures.

The breakthrough in L. monocytogenes differentiation

A major step was achieved in 2015 by continuous expansion of the MALDI Biotyper reference library with new Listeria strains and species, allowing identification to the species level using the extraction protocol for sample preparation. This differentiation is now as easy as it can be by implementing the MBT Subtyping Module into the identification workflow, because samples can now be used without additional preparation work.

Now you can - L. monocytogenes differentiation without major efforts

With the MBT Subtyping Module, the sample mass spectrum is thoroughly compared with characteristic peaks in all Listeria spectra of the reference library, using sophisticated bioinformatics. This allows using the easy-to-apply direct transfer sample transfer method instead of more labor-intensive preparation methods. This, and the high accuracy of the method, enables QC control laboratories to implement testing on L. monocytogenes in the daily routine without major efforts.

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Identification results to the species level for L. monocytogenes, using the MBT Subtyping Module.