Listeriosis and the COVID-19 pandemic

Listeriosis is a saprozoonotic infection that occurs when eating foods contaminated with Listeria. Invasive forms of listeriosis can have extremely severe consequences. Respiratory viral diseases predispose to the occurrence of combined viral-bacterial infections. With a mixed infection of listeriosis and COVID-19, a severe course of the disease is observed, which has a serious prognosis. The aim of the study was to analyze the frequency of various variants of invasive listeriosis and their outcomes in the period before the COVID-19 pandemic and against the background of its development, as well as to determine the genetic diversity of L. monocytogenes isolates. Material and methods. We analyzed 55 cases of invasive listeriosis in patients observed in 2018-2021 in various medical organizations in Moscow. The diagnosis was established on the basis of epidemiological, clinical and laboratory data, listeriosis was confirmed by bacteriological and molecular genetic methods, COVID-19 was confirmed by the detection of SARS-CoV-2 RNA in an oropharyngeal swab using real-time RT-PCR, as well as computed tomography of the lungs. Results. During the current COVID-19 pandemic (2020-2021), the incidence of listeriosis in pregnant women and invasive listeriosis occurring in the form of sepsis and/or lesions of the central nervous system did not differ significantly from similar indicators registered in 2018-2019. Listeria sepsis and/or meningitis/meningoencephalitis in association with severe SARS-CoV-2 novel coronavirus infection are at high risk of death. During the years of the COVID-19 pandemic, the diversity and range of L. monocytogenes genotypes in invasive listeriosis changed, new genotypes appeared that were not previously characteristic of the Russian Federation. Conclusion. The likelihood of developing listeriosis sepsis and/or meningitis/meningoencephalitis against the background of a severe course of COVID-19, and a high risk of an adverse outcome, require increased awareness of medical workers in the field of diagnosis and treatment of invasive listeriosis in order to conduct the earliest and most adequate antibiotic therapy. © 2022 Geotar Media Publishing Group. All Rights Reserved.