# Listeria monocytogenes and Listeria ivanovii Virulence and Adaptations Associated with Leafy Vegetables from Small-Scale Farm and a Shift of Microbiota to a New Niche at Markets: A Systematic Review

## TL;DR

This review examines how Listeria species, especially L. monocytogenes and L. ivanovii, adapt and spread through leafy vegetables from small farms to markets, posing health and economic risks.

## Contribution

The study systematically reviews virulence and adaptation mechanisms of Listeria in leafy vegetables and their transition to market environments.

## Key findings

- ST5, ST121, and ST321 are predominant and virulent Listeria strains found in ready-to-eat foods.
- ST1, ST2, and ST204 are hypervirulent strains in food processing environments.
- Listeria infections pose severe risks to immunocompromised individuals and cause economic losses due to sanitation shutdowns.

## Abstract

The study conducted a review of Listeria prevalence, virulence, and adaptations associated with leafy vegetables from small-scale farms and their journey to markets. PubMed, Taylor and Francis, Oxford, and Google Scholar databases were utilised to search for English-language journal articles published between January 1992 and 2025. Studies utilised multi-locus sequence typing (MLST), polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP), multiplex PCR, pulsed-field gel electrophoresis (PFGE), and whole genome sequencing WGS, confocal scanning laser microscopy technique for the detection of Listeria species, followed by transcriptomic, phenotypic analyses, strand-specific RNA-sequencing, and membrane lipid profiling. ST5, ST121, and ST321 are considered predominant and virulent and have been identified in two ready-to-eat commodities, while ST1, ST2, and ST204 are considered hypervirulent strains in food processing environments. Immunocompromised groups can experience severe life-threatening infections, even death. Significant economic losses due to shutdowns for sanitary procedures can occur, impacting food security.