Environmental persistence of Listeria monocytogenes and its implications in dairy processing plants

Abstract

Listeriosis, an invasive illness with a fatality rate between 20% and 30%, is caused by the ubiquitous bacterium Listeria monocytogenes. Human listeriosis has long been associated with foods. This is because the ubiquitous nature of the bacteria renders it a common food contaminant, posing a significant risk to the food processing sector. Although several sophisticated stress coping mechanisms have been identified as significant contributing factors toward the pathogen's persistence, a complete understanding of the mechanisms underlying persistence across various strains remains limited. Moreover, aside from genetic aspects that promote the ability to cope with stress, various environmental factors that exist in food manufacturing plants could also contribute to the persistence of the pathogen. The objective of this review is to provide insight into the challenges faced by the dairy industry because of the pathogens’ environmental persistence. Additionally, it also aims to emphasize the diverse adaptation and response mechanisms utilized by L. monocytogenes in food manufacturing plants to evade environmental stressors. The persistence of L. monocytogenes in the food processing environment poses a serious threat to food safety and public health. The emergence of areas with high levels of L. monocytogenes contamination could facilitate Listeria transmission through aerosols, potentially leading to the recontamination of food, particularly from floors and drains, when sanitation is implemented alongside product manufacturing. Hence, to produce safe dairy products and reduce the frequency of outbreaks of listeriosis, it is crucial to understand the factors that contribute to the persistence of this pathogen and to implement efficient control strategies.

Unveiling a Listeria monocytogenes Outbreak in a Rabbit Farm: Clinical Manifestation, Antimicrobial Resistance, Genomic Insights and Environmental Investigation

“…The identification of a cluster on the rabbit farm indicates the bacteria's circulation within the farm, possibly facilitated by workers' movement, suggesting that the implemented biosecurity measures may require further enhancements. The detection of L. monocytogenes in various environmental samples, including walls, feeders, flooring, cages from the maternity unit, water from the fattening unit, and sheep faeces, highlights its ubiquitous presence and environmental persistence [59,60], creating uncertainty about its origin. Whether the environment serves as a potential source of Listeria spp.…”

Exploring the occurrence of Listeria in biofilms and deciphering the bacterial community in a frozen vegetable producing environment

“…Listeria (L.) monocytogenes is of particular concern due to its versatility and ability to adapt to harsh environmental conditions such as low temperatures ( Schmid et al, 2009 ; Muchaamba et al, 2022 ; Osek et al, 2022 ). L. monocytogenes is further able to persist for years in diverse food processing environments despite hygiene measures ( Guidi et al, 2021 ; Chen et al, 2022 ; Sullivan et al, 2022 ; Chowdhury and Anand, 2023 ; Schiavano et al, 2023 ) elevating the risk of food contamination. Long-term survival of L. monocytogenes has been previously linked to gene content involved in stress resistance, which provides tolerance against disinfectants, a wide range of temperatures, acidic and alkaline conditions, and high salinity ( Bucur et al, 2018 ; Lakicevic et al, 2022 ).…”