Genomic Characteristics of listeria that Caused Invasive listeriosis During the COVID-19 Pandemic

Abstract

Invasive listeriosis is relatively rare, but is one of the deadliest food-borne infections, affecting pregnant women, their fetuses and newborn infants, the elderly and immunocompromised people. The aim of this study was to research the impact of the COVID-19 pandemic on invasive listeriosis in the metropolis. Loci and whole-genome sequencing with subsequent bioinformatic analysis were used for the study of clinical and food <em>Listeria monocytogenes</em> isolates revealed in 2018–2022. The results indicate the crucial change in the spectrum of the <em>L. monocytogenes</em>se quence types (ST) causing invasive listeriosis during the COVID-19 pandemic, with slight changes in the ST spectrum of the food isolates. An increase in sensitivity to previously non-human <em>L. monocytogenes</em> genotypes, namely ST8, 21, 37, 391, and 425, was observed. <em>L. monocytogenes</em> of ST20 and 425 carried plasmids with virulence factors (VF), in addition to the 42 VF identified in the genomes with the <em>vip</em> gene exclusion in the genomes of ST7, 8, 21, and 37. Perinatal listeriosis cases were associated with the new hypervirulent <em>L. monocytogenes</em> of ST1, 4, and 219 compiled with old ST6. These data indicate the need for the more stringent control of food products for high-risk groups.