Retrospective Study of Listeria Monocytogenes Isolated in the Territory of Inner Eurasia from 1947 to 1999

Abstract

Listeriosis is one of the most significant humans and animals foodborne infectious diseases. Here, we characterized 48 Listeria monocytogenes strains isolated in the territory of inner Eurasia during the second half of the 20th century. A total of 23 strains (52.3%) were susceptible to the nine antibiotics tested, 30.43%, 15.22%, and 8.7% were resistant penicillin G, ampicillin, and enrofloxacin, respectively. We applied the multilocus sequence typing (MLST) scheme to determine the phylogenetic positions of the strains. All but one strain belonged to the II phylogenetic lineage, and the majority of the strains belonged to one of the previously described clonal complexes (СCs). More than 60% of the strains belonged to the clonal complex CC7 that prevailed among all sources, including cattle (58%), small ruminants (64%), rodents (71%), and humans (50%). Further, CC7, CC101, and CC124 were found among human isolates. The MLST scheme was supplemented with virulence gene analysis. In total, eight inlA, six inlB, and six inlC allelic variants were found, and all but one strain carried one of the two inlE alleles. Most strains (62.5%) belonged to the same multivirulence locus sequence typing (MvLST) type, which includes CC7, inlA allele 4, inlB allele 14, inlC allele 6, and inlE allele 8.

Novel Sequence Types of Listeria monocytogenes of Different Origin Obtained in the Republic of Serbia

“…Microorganisms 2021, 9, 1289 8 of 17 ST1242) except the only ST1234 (CC5), which was detected in a food specimen (Table S1, Supplemental Data 1). Interestingly, previous epidemiologic studies demonstrated that lineage I is generally overrepresented among human clinical listeriosis cases, while lineage II strains were found to be major contaminants of food products [5,9,19]. However, in fact, among the Serbia-2019 strains, non-human clinical isolates of animal and food origin belonging to lineage I were first detected (Table 1).…”

“…L. monocytogenes is amongst the major food-borne pathogens in the world and has attracted much research attention from public health, veterinary medicine, and food authorities over the recent decades [3]. L. monocytogenes has been linked to sporadic episodes, as well as large outbreaks, of human listeriosis worldwide [4,5]. Although relatively rare (the annual incidence rate ranges from 0.2 to 0.5 cases per 100,000 population), listeriosis is responsible for high hospitalization rates of over 95% and mortality rates (average fatality rates are estimated to be 20-30% of hospitalized patients and can reach 40% in outbreaks related to foodborne infections) [5,6].…”

“…L. monocytogenes has been linked to sporadic episodes, as well as large outbreaks, of human listeriosis worldwide [4,5]. Although relatively rare (the annual incidence rate ranges from 0.2 to 0.5 cases per 100,000 population), listeriosis is responsible for high hospitalization rates of over 95% and mortality rates (average fatality rates are estimated to be 20-30% of hospitalized patients and can reach 40% in outbreaks related to foodborne infections) [5,6]. For example, within the European Union, the case fatality for L. monocytogenes-associated infection stood at 15.6% in 2018 [7].…”

Listeriosis: genotyping as a key for identification a possible source of infection

“…Сомова на дальневосточных штаммах L. monocytogenes [20], были продолжены в работах НИЦЭМ им Н.Ф. Гамалеи с ФИЦВиМ на штаммах коллекции ФИЦВиМ XXI века [21,24], также XX века [22]. Сотрудниками ГНЦ прикладной микробиологии и биотехнологии (Оболенск, Россия) были исследо-ваны клинические изоляты 2015-2017 гг., два изолята из окружающей среды 2018 г., а также изоляты из продуктов питания 2017 г.…”

“…разработан подход для типирования локусов вирулентности, включающих фрагменты генов интерналинов, -MvLST (Multi-virulent-locus sequence typing) [19][20][21][22]. Дальнейшие исследования изолятов листерий [21][22][23][24] пополнили список аллелей интерналинов (Inl) A, B, C, E и интерналиновых профилей (IP). Широта исследования, охват изолятов европейской части России и Дальневосточного федерального округа (ДФО) стали возможны благодаря многоцентровому сотрудничеству (НИЦЭМ им.…”