Partial sequencing reveals the existence of one BTV-4 strain on whole territory of Macedonia during 2014 outbreak (original) (raw)
Related papers
The foodborne pathogen Listeria monocytogenes is also widely spread in nature. We report a survey of L.monocytogenes in Natural Parks of the densely populated Central Federal Region of Russia. Our study revealed the prevalence of phylogenetic lineage II, serovar 1/2a isolates, further classified into 11 sequence types (STs), three of which (756, 757, 758) we first described. Only one isolate from the dappled deer's faeces belonged to the phylogenetic lineage I, serovar 1/2b (ST5). All novel STs were single locus variants of known STs. Five STs belonged to the previously established epidemic clones VII, V, VI and III. Multi-virulent-locus-sequence-typing (MvLST) based on the internalins-genes-profile (IP) revealed six new IPs. Comparison of the concatenated MLST (multilocus-sequence-typing) and IP sequences of the strains from two distinct areas of Russia, the European and the Far Eastern part, demonstrated considerable differences between them. In spite of the prevalence of global STs in both areas, phylogenetic lineage I strains predominated in the Far East region, while lineage II strains were mainly isolated in the European part. Our findings highlight the importance of epidemiological monitoring of the natural foci of L.monocytogenes infection and demonstrated usefulness of the combination of MLST and IP methods for this purpose.
Pathogens
Listeria spp. is a diverse genus of Gram-positive bacteria commonly present in the environment while L. monocytogenes and L. ivanovii are well known human and ruminant pathogens. The aim of the present study was to reveal the prevalence and genetic diversity of L. monocytogenes and other Listeria spp. and to identify the factors related to the abundance of pathogen at cattle farms. A total of 521 animal and environmental samples from 27 meat and dairy cattle farms were investigated and the genetic diversity of L. monocytogenes isolates was studied with WGS. The prevalence of Listeria was 58.9%, while of L. monocytogenes it was −11%. The highest prevalence of L. monocytogenes was found in the environment—soil samples near to manure storage (93%), mixed feed from the feeding trough and hay (29%), water samples from farms drinking trough (28%) and cattle feces (28%). Clonal complexes (CC) of CC37 (30%), CC11 (20%) and CC18 (17%) (all IIa serogroup) were predominant L. monocytogenes clo...
Phylogenetic positioning of Listeria ivanovii identified in aborted sheep in Kars Region (Turkey)
The Thai Journal of Veterinary Medicine
This study aimed to investigate Listeria species in various samples taken from aborted sheep in Kars province and to determine the position of emerged strains in the phylogenetic tree. Milk (n= 229) and vaginal swab (n= 263) samples from aborted sheep and abomasum contents (n= 46) of aborted sheep fetuses were investigated by the culture and Polymerase Chain Reaction (PCR) methods. For the phylogenetic analysis of isolates, the 16S rRNA gene region was sequenced. In the culture, the Listeria agent was not isolated from any of the vaginal swabs or milk samples. Among the 46 fetal abomasum contents, a Listeria suspicious colony was obtained from only one (2.17%) sample which belonged to an enterprise with a history of silage feeding. This isolate was identified as Listeria ivanovii by both conventional methods and genus and species-specific PCR. In addition, Listeria DNA was detected in a total of 8 (1.48%) samples (in 1 vaginal swab, 1 milk and 6 fetal abomasum samples) by direct genus-specific PCR. However, these samples could not be identified, except for one of the 6 abomasum content samples that was found as L. ivanovii. The L. ivanovii isolate was double-identified after the amplification of the 16S rRNA gene region followed by sequence analysis. Sequence analysis of the 16S rRNA gene region gave a phylogenetic position to the isolate, L. ivanovii, which had been scarcely identified from the abortive specimens.
Listeria ivanovii and L. monocytogenes, are the only pathogenic species of the genus Listeria and share many virulence factors and mechanisms of pathogenicity. L. ivanovii shows host tropism towards small ruminants and rodents and much lower virulence for humans compared to L. monocytogenes. However, severe infections caused by L. ivanovii, resulting in bacteremia, abortion and stillbirth, occasionally occurred in immunocompromised persons and in pregnant women, while in immunocompetent hosts L. ivanovii can cause gastroenteritis. In this review the updated knowledge on virulence aspects and distribution of L. ivanovii in the environment and in food are summarized. Recent research on its virulence characters at genome level gave indications on how pathogenicity evolved in this bacterial species. As for L. monocytogenes, L. ivanovii infections occur after the ingestion of contaminated food, so an overview of reports regarding its distribution in the food products was carried out to o...
2004
Twenty six Listeria monocytogenes strains were isolated from foodstuffs and animal clinical cases and analysed by genotyping including ITS profiling, REP-and ERIC-PCR and PFGE. Analysis of DNA banding generated by ITS profiling revealed the presence of just three different genotypes. With the use of REP-PCR, ten different DNA patterns could be discriminated among the analysed isolates. ERIC-PCR and PFGE gave similar results. With the first method, 13 different DNA patterns were found, with the latter one-14 different genotypes. Based on data obtained by the ERIC-PCR and PFGE it was shown that the majority of food-derived L. monocytogenes represent different genotypes than clinical isolates recovered from infected animals.
Listeria valentina sp. nov., isolated from a water trough and the faeces of healthy sheep
International Journal of Systematic and Evolutionary Microbiology
In the context of a study on the occurrence of Listeria species in an animal farm environment in Valencia, Spain, six Listeria -like isolates could not be assigned to any known species. Phylogenetic analysis based on the 16S rRNA gene and on 231 Listeria core genes grouped these isolates in a monophyletic clade within the genus Listeria , with highest similarity to Listeria thailandensis . Whole-genome sequence analyses based on in silico DNA–DNA hybridization, the average nucleotide blast and the pairwise amino acid identities against all currently known Listeria species confirmed that these isolates constituted a new taxon within the genus Listeria . Phenotypically, these isolates differed from other Listeria species mainly by the production of acid from inositol, the absence of acidification in presence of methyl α-d-glucoside, and the absence of α-mannosidase and nitrate reductase activities. The name Listeria valentina sp. nov. is proposed for this novel species, and the type s...
2019
The presence of Listeria monocytogenes was evaluated in a small-scale meat processing facility in Montenegro during 2011-2014. L. monocytogenes isolates from traditional meat products and environmental swabs were subjected to a) molecular characterization b) serotyping by both multiplex PCR and next generation sequencing (NGS) c) potential antimicrobial resistance (AMR) was assessed by extraction of specific genes from NGS data and d) screening for the presence of some disinfectant resistance markers. Overall, traditional meat products were contaminated, most likely from incoming raw materials, with 4 major specific STs of L. monocytogenes (ST515, ST8, ST21, ST121) representing 4 clonal complexes (CC1, CC8, CC21, CC121) identified during the four-year period. These strains belonged to serogroup IIa which predominated, followed by IVb (ST515, CC1). The strains from environmental swabs belonged, exclusively, to ST21 and were isolated from cutting board and floor swabs in 2011. Further...
Analysis of Circulating Strains, Causing Invasive Listeriosis in Bulgaria for Ten Years, 2010-2019
PROBLEMS of Infectious and Parasitic Diseases
Listeriosis is a zoonosis with multiple mechanisms of infection and multiple organ symptoms, severe course and high lethality. An increasing incidence of listeriosis has been reported in several European countries in recent years. A limited range of Listeria strains is responsible for most blasts occurring in different countries. The aim of the study is to monitor the spread of the Listeria strains causing invasive listeriosis in Bulgaria for the period 2010-2019 and to analyze the etiological structure of the infection in different hospitals in the country. A total of 56 strains Listeria from 17 hospitals were investigated for confirmation of species and serogroup. The materials were isolated from haemocultures, fetuses water, cerebrospinal fluids and anal and throat secretions and two tests were used. Confirmed strains isolated from the clinical samples for the study period belonged to 4 serogroups of Listeria. Listeria monocytogenes serogroup I was detected in 28 (50%) of the sam...