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1.
Vet Anim Sci ; 19: 100276, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36545353

RESUMO

Listeria innocua is considered as non-pathogenic bacteria living in an environment although several cases of immunocompromised humans and ruminant listeriosis infections have been reported. Previously, L. innocua was identified as a potential pathogen and virulence in association with L. monocytogenes PrfA dependent virulence (LIPI-1) gene cluster was demonstrated in hemolytic L. innocua. L. innocua usually considered non-pathogenic versus pathogenic L. monocytogenes and L. ivanovii because of the main virulence gene loss. There are limited studies and reports available about L. innocua-caused illness in cattle. A total of 18 STs were identified in cattle abortions while 17 STs in the farm environment with majority of STs were present in both abortions and environmental samples. Genome sequencing showed that in one farm identical L. innocua clones were represented in water, feed, soil, and faeces sample groups, suggesting that animals most likely through the faecal shedding may remain as the main source of L. innocua in a farm environment. Out of all L. innocua isolates PrfA-dependent virulence genes were not found in aborted foetuses isolates and environmental L. innocua isolate groups; however, in 20% of isolates a complete LIPI-3 pathogenicity island encoding listeriolysin S was identified. In this study, we demonstrated that genetically diverse L. innocua clones were widely distributed in cattle farm environment and certain isolates had a significant pathogenicity potential for cattle, thus causing adverse health effects, including abortions.

2.
Int J Food Microbiol ; 376: 109756, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-35661554

RESUMO

Yersinia enterocolitica is an important zoonotic foodborne pathogen that could be transferred from infected pigs to their carcasses at slaughter, with subsequent introduction of the pathogen into the food chain. The aim of the present study was to study the prevalence, virulence characteristics, and genetic diversity of Y. enterocolitica isolates present in slaughtered pig tonsils and carcasses by using the WGS approach. A total of 200 slaughtered pig tonsils from 11 pig farms were collected in 2020-2021 at six slaughterhouses located in Latvia. Out of these samples, n = 190 were obtained from slaughtered pigs raised on Latvian farms while n = 10 were of Lithuanian origin, with the number of farms sampled being 10 and 1, respectively. Additionally, 30 pig carcasses were sampled at five slaughterhouses from pigs originating from five farms in 2021. Samples were investigated microbiologically, Y. enterocolitica isolates were biotyped and serotyped. Y. enterocolitica 4/O:3 was screened for antimicrobial resistance with the EUVSEC test panels. Whole genome sequence analysis (WGS) was performed in order to detect virulence genes and to assess the genetic diversity of Y. enterocolitica isolates. A total of 139 isolates, including one to three isolates from 84 Y. enterocolitica positive slaughtered pig tonsils and 13 pig carcass samples, were subjected to WGS analysis. The prevalence of Y. enterocolitica 4/O:3 in slaughtered pig tonsils and carcasses was 35% (70/200) and 13% (4/30), respectively. Antimicrobial resistance to ampicillin and tetracycline was detected in 97% (72/74) and 1% (1/74) of Y. enterocolitica 4/O:3 isolates. Y. enterocolitica 4/O:3 was represented only by ST18, while Y. enterocolitica 1A by ST3, ST147, ST304, ST307, and ST473. The ST18 isolates harbored the same main chromosomal (ail, inv, myfA, ystA) and majority shared plasmid-borne virulence genes (virF, yadA, yop virulon). The main virulence genes were not identified within the STs of Y. enterocolitica 1A and only minor differences were found between ST3, ST147, ST304, ST307, and ST473. Among ST18 isolates, cgMLST analysis revealed 43 cgMLST genotypes while 16 cgMLST genotypes were found among Y. enterocolitica 1A STs. The present study has shown the distribution of genetically distant cgMLST genotypes in slaughtered pigs from pig farms located in different geographical regions of Latvia, with one to 11 cgMLSTs identified within each sampled farm. The presence of undistinguishable cgMLST genotypes in slaughtered pig tonsils and the respective carcasses supported the link between the slaughter of Y. enterocolitica - positive pigs and carcass contamination with Y. enterocolitica 4/O:3.


Assuntos
Doenças dos Suínos , Yersiniose , Yersinia enterocolitica , Animais , Antibacterianos , Variação Genética , Prevalência , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/microbiologia , Virulência/genética , Fatores de Virulência/genética , Yersiniose/microbiologia , Yersinia enterocolitica/genética
3.
Vet Sci ; 8(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34564589

RESUMO

Listeria monocytogenes can cause disease in humans and in a wide range of animal species, especially in farm ruminants. The aim of the study was to determine the prevalence and genetic diversity of L. monocytogenes related to 1185 cattle abortion cases in Latvia during 2013-2018. The prevalence of L. monocytogenes among cattle abortions was 16.1% (191/1185). The seasonality of L. monocytogenes abortions was observed with significantly higher occurrence (p < 0.01) in spring (March-May). In 61.0% of the cases, the affected cattle were under four years of age. L. monocytogenes abortions were observed during the third (64.6%) and second (33.3%) trimesters of gestation. Overall, 27 different sequence types (ST) were detected, and four of them, ST29 (clonal complex, CC29), ST37 (CC37), ST451 (CC11) and ST7 (CC7), covered more than half of the L. monocytogenes isolates. Key virulence factors like the prfA-dependent virulence cluster and inlA, inlB were observed in all the analyzed isolates, but lntA, inlF, inlJ, vip were associated with individual sequence types. Our results confirmed that L. monocytogenes is the most important causative agent of cattle abortions in Latvia and more than 20 different STs were observed in L. monocytogenes abortions in cattle.

4.
Pathogens ; 10(7)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34358001

RESUMO

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 clones. CC18, CC37 and CC8 were isolated from case farms and CC37, CC11 and CC18 from farms without listeriosis history. Only one hypervirulent CC4 (1%) was isolated from the case farm. Sequence types (STs) were not associated with the isolation source, except for ST7, which was significantly associated with soil (p < 0.05). The contamination of soil, feeding tables and troughs with L. monocytogenes was associated with an increased prevalence of L. monocytogenes at farms. Our study indicates the importance of hygienic practice in the prevention of the dissemination of L. monocytogenes in the cattle farm environment.

5.
Microorganisms ; 9(8)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34442743

RESUMO

Alaria (A.) alata mesocercariae (AM) have increasingly appeared as incidental findings during the mandatory inspection of wild boars for Trichinella in many European countries. An Alaria spp.-specific PCR is available for the identification of AM; however, it is time- and cost-intensive. Therefore, we propose a rapid and cost-efficient MALDI-TOF assay for the identification of AM in wild boar meat that can be applied in routine diagnostics. In this study, a fast and methodologically simple protocol for the protein extraction of AM from different host species in different countries was established, and an AM-specific reference spectra database was created as part of the ongoing development of an existing Trichinella spp. database. A formic acid protein extraction was performed after pooling 10 AM from the same host individual. In total, 61 main spectra profiles (MSPs) from different host individuals were stored in an AM-specific MSP library. The cluster analysis of these 61 MSPs indicated a possible variation within the A. alata species with a tentative association with the geographical origin of the host, but not the host species. This MALDI-TOF assay allows for a fast verification of the AM isolates, which is the next step in the development of a universal database for the identification of several parasites isolated from meat.

6.
Pathogens ; 11(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35055985

RESUMO

Yersinia enterocolitica is an important foodborne pathogen, and the determination of its virulence factors and genetic diversity within the food chain could help understand the epidemiology of yersiniosis. The aim of the present study was to detect the prevalence, and characterize the virulence determinants and genetic diversity, of Yersinia species isolated from meat. A total of 330 samples of retailed beef (n = 150) and pork (n = 180) in Latvia were investigated with culture and molecular methods. Whole genome sequencing (WGS) was applied for the detection of virulence and genetic diversity. The antimicrobial resistance of pathogenic Y. enterocolitica isolates was detected in accordance with EUCAST. Yersinia species were isolated from 24% (79/330) of meats, and the prevalence of Y. enterocolitica in pork (24%, 44/180) was significantly higher (p < 0.05) than in beef (13%, 19/150). Y. enterocolitica pathogenic bioserovars 2/O:9 and 4/O:3 were isolated from pork samples (3%, 6/180). Only resistance to ampicillin was confirmed in Y. enterocolitica 4/O:3 and 2/O:9 isolates, but not in other antimicrobials. Major virulence determinants, including ail, inv, virF, ystA and myfA, were confirmed with WGS in Y. enterocolitica 2/O:9 and 4/O:3. MLST typing revealed 15 STs (sequence types) of Y. enterocolitica with ST12 and ST18, which were associated with pathogenic bioserovars. For Y. enterocolitica 1A, Y. kristensenii, Y. intermedia and Y. frederiksenii, novel STs were registered (ST680-688). The presence of virulence genes and genetic characteristics of certain Y. enterocolitica STs confirm the common knowledge that pork could be an important source of pathogenic Yersinia.

7.
Toxins (Basel) ; 12(9)2020 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-32872457

RESUMO

In this paper, a study of fungal and multi-mycotoxin contamination in 140 Camellia sinensis and 26 herbal teas marketed in Latvia is discussed. The analysis was performed using two-dimensional liquid chromatography with time-of-flight mass spectrometry (2D-LC-TOF-MS) and MALDI-TOF-MS. In total, 87% of the tea samples tested positive for 32 fungal species belonging to 17 genera, with the total enumeration of moulds ranging between 1.00 × 101 and 9.00 × 104 CFU g-1. Moreover, 42% of the teas (n = 70) were contaminated by 1 to 16 mycotoxins, and 37% of these samples were positive for aflatoxins at concentrations ranging between 0.22 and 41.7 µg kg-1. Deoxynivalenol (DON) and its derivatives co-occurred in 63% of the tea samples, with their summary concentrations reaching 81.1 to 17,360 µg kg-1. Ochratoxin A (OTA), enniatins, and two Alternaria toxins were found in 10-37% of the teas at low concentrations. The dietary exposure assessment based on the assumption of a probable full transfer of determined mycotoxins into infusions indicated that the analysed teas are safe for consumers: the probable maximum daily exposure levels to OTA and the combined DON mycotoxins were only 0.88 to 2.05% and 2.50 to 78.9% of the tolerable daily intake levels.


Assuntos
Camellia sinensis/microbiologia , Exposição Dietética , Fungos/metabolismo , Micotoxinas/análise , Chá/microbiologia , Chás de Ervas/microbiologia , Cromatografia Líquida , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor , Exposição Dietética/efeitos adversos , Humanos , Letônia , Micotoxinas/efeitos adversos , Medição de Risco , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
8.
Foodborne Pathog Dis ; 17(7): 420-428, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31895586

RESUMO

Microgreens and sprouts have been used for raw consumption for a long time and are generally viewed as a healthy food. However, several serious outbreaks of foodborne illness have been recorded in European countries, Japan, and North America. Many companies in Latvia nowadays are producing this type of products. The aim of this study was to characterize the incidence of Shiga toxin-producing Escherichia coli (STEC), Salmonella spp., and Listeria spp. in microgreens, sprouts, and seeds intended for domestic production of microgreens on retail market in Riga, Latvia, from January to April 2019. The background microflora was identified as well. A total of 45 samples were purchased, including fresh and processed sprouts, microgreens, baby greens, as well as seeds intended for domestic production of microgreens and sprouts. The samples were processed according to the methods set by the International Organization for Standardization (ISO)-ISO/TS 13136:2012 for STEC, ISO 6579-1:2017 for Salmonella spp., and ISO 11290-1:2017 for Listeria spp. Molecular detection of Salmonella spp. was also performed using real-time polymerase chain reaction. The typical and atypical colonies isolated from selective plates were identified with matrix-assisted laser desorption and ionization time-of-flight mass spectrometry. Listeria monocytogenes was not detected in any of the tested samples. However, the presence of Listeria innocua was detected in two (4.4%) of the samples. Three (6.7%) samples of dried sprouts were positive for the STEC virulence genes. Salmonella spp. was detected in one (2.2%) sample of common sunflower seeds. Altogether, 46 different background bacterial species were identified. The majority were environmental bacteria characteristic to soil, water, and plants, including coliform bacteria. The results provide evidence that microgreens and seeds available for Latvian consumers are generally safe, however, attention has to be paid to dried sprouts.


Assuntos
Microbiologia de Alimentos/estatística & dados numéricos , Brotos de Planta/microbiologia , Plântula/microbiologia , Supermercados , Verduras/microbiologia , Contagem de Colônia Microbiana , Incidência , Letônia/epidemiologia , Listeria/isolamento & purificação , Salmonella/isolamento & purificação , Escherichia coli Shiga Toxigênica/isolamento & purificação
9.
Clin Mass Spectrom ; 16: 33-39, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34820518

RESUMO

Rapid identification of methicillin-resistant Staphylococcus could ensure appropriate medical care. A total of 409 Staphylococcus spp. strains were used to develop a reliable MALDI-TOF method for species identification. We tested twelve S. aureus strains to compare three different sample preparation methods and the reproducibility of the methicillin-resistant m/z 2414 ± 2 indicator peak with direct method in triplicate. A total of 65 Staphylococcus spp. strains (including 37 methicillin-resistant strains) from clinical and hospital environment isolates were used to confirm the presence of phenol-soluble modulin (PSM-mec) peptide. All 272 S. aureus strains from 409 samples were correctly identified at species level by MALDI-TOF. The samples prepared by three methods gave spectra with differences in the intensities and presence of certain peaks. The PSM-mec peak was not visible after the extraction method. The peak m/z 2414 ± 2 was only detected in 61% of the methicillin-resistant strains and in none of the methicillin-sensitive strains. The peak reproducibility for the five analyzed S. aureus strains showing the peak at m/z 2414 ± 2 was 87%. The delta-toxin was observed in 49 out of 65 samples regardless of methicillin susceptibility, as well as in all the samples exhibiting the PSM-mec peak. The peak m/z 2414 ± 2 is specific to methicillin-resistant strains carrying the mecA gene, but the absence of peak m/z 2414 ± 2 does not exclude the possibility of resistance to methicillin. Thus, implementing MALDI-TOF analysis in routine laboratory work, especially with clinical samples, would in many cases provide rapid warning about the presence of methicillin-resistant strains.

10.
Euro Surveill ; 24(31)2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31387670

RESUMO

BackgroundCampylobacter is the main cause of bacterial gastroenteritis worldwide. The main transmission route is through consumption of food contaminated with Campylobacter species or contact with infected animals. In Latvia, the prevalence of campylobacteriosis is reported to be low (4.6 cases per 100,000 population in 2016).AimTo determine prevalence, species spectrum and antimicrobial resistance (AMR) of Campylobacter spp. in Latvia, using data from various livestock and human clinical samples.MethodsWe analysed data of Campylobacter microbiological monitoring and AMR (2008 and 2014-16) in Latvia. Data from broilers, poultry, pigs, calves and humans were used to determine prevalence of Campylobacter. Additionally, 45 different origin isolates (22 human) were sequenced on the Illumina MiSeq platform; for each isolate core genome multilocus sequence typing was used and relevant antimicrobial resistance mechanisms were identified.ResultsOverall, Campylobacter prevalence in was 83.3% in pigs, 50.2% in broilers, 16.1% in calves and 5.3% in humans; C. jejuni was the predominant species in all sources except pigs where C. coli was main species. High level of resistance in Campylobacter were observed against fluoroquinolones, tetracycline and streptomycin, in most of sequenced isolates genetic determinants of relevant AMR profiles were identified.ConclusionsIn Latvia, prevalence of Campylobacter in livestock is high, especially in pigs and broilers; prevalence in poultry and humans were lower than in other European countries. AMR analysis reveals increase of streptomycin and tetracycline resistant broiler origin C. jejuni strains. WGS demonstrates a high compliance between resistance phenotype and genotype for quinolones and tetracyclines.


Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/tratamento farmacológico , Campylobacter coli/efeitos dos fármacos , Campylobacter coli/genética , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana Múltipla/genética , Animais , Infecções por Campylobacter/diagnóstico , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/veterinária , Campylobacter coli/isolamento & purificação , Campylobacter jejuni/isolamento & purificação , Bovinos , Galinhas/microbiologia , Ciprofloxacina/farmacologia , Clindamicina/farmacologia , Eritromicina/farmacologia , Genótipo , Gentamicinas/farmacologia , Humanos , Letônia/epidemiologia , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Aves Domésticas/microbiologia , Prevalência , Vigilância de Evento Sentinela , Suínos/microbiologia , Tetraciclinas/farmacologia , Sequenciamento Completo do Genoma
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