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1.
Microbiol Spectr ; 12(1): e0341823, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38063356

RESUMO

IMPORTANCE: This study is important because it shows the potential epidemiological silence associated with the use of culture as the primary diagnostic method for the laboratory identification of human campylobacteriosis. Also, we show how polymerase chain reaction methods are associated with a systematic increase in the number of human campylobacteriosis episodes as reported by routine disease surveillance. These findings are operationally relevant and have public health implications because they tell how crucial it is to consider changes in diagnostic methods, e.g., in the epidemiological analysis of historical data and in the interpretation of future data in light of the past. We also believe that this study highlights how the synergy between microbiology and epidemiology is essential for disease surveillance.


Assuntos
Infecções por Campylobacter , Campylobacter , Gastroenterite , Humanos , Infecções por Campylobacter/diagnóstico , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Estudos Retrospectivos , Campylobacter/genética , Dinamarca/epidemiologia , Reação em Cadeia da Polimerase
2.
Sci Data ; 10(1): 833, 2023 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012190

RESUMO

Knowledge about local air temperature variations and extremes in Antarctica is of large interest to many polar disciplines such as climatology, glaciology, hydrology, and ecology and it is a key variable to understand climate change. Due to the remote and harsh conditions of Antarctica's environment, the distribution of air temperature observations from Automatic Weather Stations is notably sparse across the region. Previous studies have shown that satellite-derived land and ice surface temperatures can be used as a suitable proxy for air temperature. Here, we developed a daily near-surface air temperature dataset, AntAir ICE for terrestrial Antarctica and the surrounding ice shelves by modelling air temperature from MODIS skin temperature for the period 2003 to 2021 using a linear model. AntAir ICE has a daily temporal resolution and a gridded spatial resolution of 1 km2. AntAir ICE has a higher accuracy in reproducing in-situ measured air temperature when compared with the well-established climate re-analysis model ERA5 and a higher spatial resolution which highlights its potential for monitoring temperature patterns in Antarctica.

3.
Children (Basel) ; 10(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37628326

RESUMO

Cognitive biases toward disorder-specific stimuli are suggested as crucial to the development and maintenance of symptoms in adults with functional gastrointestinal disorders (FGID). Functional abdominal pain disorders (FAPD), a subtype of FGID, are common in children and adolescents, but the influence of cognitive biases is sparsely examined. This study aimed to (1) develop a new experimental design for assessing cognitive biases toward gastrointestinal stimuli in children and adolescents (aged 8 to 17 years) and (2) derive comparative data on bias toward gastrointestinal stimuli using a healthy "normative" sample. The online experimental design-BY-GIS (Bias in Youth toward GastroIntestinal-related Stimuli)-includes a word task and a picture task. Stimuli in both tasks are related to general and gastrointestinal symptoms, and the design includes three phases: (1) encoding, (2) free recall, and (3) recognition. Data were collected between April 2022 and April 2023 from 96 healthy participants (Mage = 12.32, 47.92% female). Adolescents were significantly better at recalling words than children (p = 0.03), whereas there were no significant gender or age differences with regard to recalling pictures (p > 0.05). Across age and gender, participants performed above chance level in the recognition phases of both tasks. The results support that the design is suitable within the age span.

4.
Ugeskr Laeger ; 185(22)2023 05 29.
Artigo em Dinamarquês | MEDLINE | ID: mdl-37264858

RESUMO

This review summarises the current knowledge of whole genome sequencing (WGS) which has become the standard method for genetic characterisation of bacteria in surveillance and outbreak investigation. Although the method offers many advantages, its use in outbreak investigations is hampered by the relatively slow turn-around time. Using new approaches to perform WGS, typing and gene detection can now be completed within one day. This break-through allows clinical consequences to be taken almost immediately after detection of relevant bacteria and may have a huge impact on the future prevention of transmission of infectious diseases.


Assuntos
Infecções Bacterianas , Humanos , Sequenciamento Completo do Genoma/métodos , Surtos de Doenças/prevenção & controle
5.
Appl Environ Microbiol ; 88(23): e0136822, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36354326

RESUMO

Members of the Campylobacter lari group are causative agents of human gastroenteritis and are frequently found in shellfish, marine waters, shorebirds, and marine mammals. Within a One Health context, we used comparative genomics to characterize isolates from a diverse range of sources and geographical locations within Europe and Australia and assess possible transmission of food, animal, and environmental isolates to the human host. A total of 158 C. lari isolates from Australia, Denmark, France, and Germany, which included 82 isolates from human stool and blood, 12 from food, 14 from domestic animal, 19 from waterbirds, and 31 from the environment were analyzed. Genome-wide analysis of the genetic diversity, virulence, and antimicrobial resistance (AMR) traits was carried-out. Most of the isolates belonged to C. lari subsp. lari (Cll; 98, 62.0%), while C. lari subsp. concheus and C. lari urease-positive thermotolerant Campylobacter (UPTC) were represented by 12 (7.6%) and 15 (9.5%) isolates, respectively. Furthermore, 33 (20.9%) isolates were not assigned a subspecies and were thus attributed to distant Campylobacter spp. clades. Whole-genome sequence-derived multilocus sequence typing (MLST) and core-genome MLST (cgMLST) analyses revealed a high genetic diversity with 97 sequence types (STs), including 60 novel STs and 14 cgMLST clusters (≤10 allele differences), respectively. The most prevalent STs were ST-21, ST-70, ST-24, and ST-58 (accounting for 13.3%, 4.4%, 3.8%, and 3.2% of isolates, respectively). A high prevalence of the 125 examined virulence-related loci (from 76.8 to 98.4% per isolate) was observed, especially in Cll isolates, suggesting a probable human pathogenicity of these strains. IMPORTANCE Currently, relatedness between bacterial isolates impacting human health is easily monitored by molecular typing methods. These approaches rely on discrete loci or whole-genome sequence (WGS) analyses. Campylobacter lari is an emergent human pathogen isolated from diverse ecological niches, including fecal material from humans and animals, aquatic environments, and seafood. The presence of C. lari in such diverse sources underlines the importance of adopting an integrated One Health approach in studying C. lari population structure for conducting epidemiological risk assessment. This retrospective study presents a comparative genomics analysis of C. lari isolates retrieved from two different continents (Europe and Australia) and from different sources (human, domestic animals, waterbirds, food, and environment). It was designed to improve knowledge regarding C. lari ecology and pathogenicity, important for developing effective surveillance and disease prevention strategies.


Assuntos
Infecções por Campylobacter , Campylobacter lari , Leucemia Linfocítica Crônica de Células B , Saúde Única , Animais , Humanos , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/veterinária , Infecções por Campylobacter/microbiologia , Campylobacter lari/genética , Campylobacter lari/isolamento & purificação , Genômica , Tipagem de Sequências Multilocus , Estudos Retrospectivos
6.
Nat Commun ; 13(1): 1263, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35273172

RESUMO

The transportation sector is undergoing a technology shift from internal combustion engines to electric motors powered by secondary Li-based batteries. However, the limited range and long charging times of Li-ion batteries still hinder widespread adoption. This aspect is particularly true in the case of heavy freight and long-range transportation, where solid oxide fuel cells (SOFCs) offer an attractive alternative as they can provide high-efficiency and flexible fuel choices. However, the SOFC technology is mainly used for stationary applications owing to the high operating temperature, low volumetric power density and specific power, and poor robustness towards thermal cycling and mechanical vibrations of conventional ceramic-based cells. Here, we present a metal-based monolithic fuel cell design to overcome these issues. Cost-effective and scalable manufacturing processes are employed for fabrication, and only a single heat treatment is required, as opposed to multiple thermal treatments in conventional SOFC production. The design is optimised through three-dimensional multiphysics modelling, nanoparticle infiltration, and corrosion-mitigating treatments. The monolithic fuel cell stack shows a power density of 5.6 kW/L, thus, demonstrating the potential of SOFC technology for transport applications.

7.
Microbiol Spectr ; 10(1): e0237621, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35196810

RESUMO

The Klebsiella pneumoniae species complex (KpSC) is a leading cause of multidrug-resistant human infections. To better understand the potential contribution of food as a vehicle of KpSC, we conducted a multicentric study to define an optimal culture method for its recovery from food matrices and to characterize food isolates phenotypically and genotypically. Chicken meat (n = 160) and salad (n = 145) samples were collected in five European countries and screened for the presence of KpSC using culture-based and zur-khe intergenic region (ZKIR) quantitative PCR (qPCR) methods. Enrichment using buffered peptone water followed by streaking on Simmons citrate agar with inositol (44°C for 48 h) was defined as the most suitable selective culture method for KpSC recovery. A high prevalence of KpSC was found in chicken meat (60% and 52% by ZKIR qPCR and the culture approach, respectively) and salad (30% and 21%, respectively) samples. Genomic analyses revealed high genetic diversity with the dominance of phylogroups Kp1 (91%) and Kp3 (6%). A total of 82% of isolates presented a natural antimicrobial susceptibility phenotype and genotype, with only four CTX-M-15-producing isolates detected. Notably, identical genotypes were found across samples-same food type and same country (15 cases), different food types and same country (1), and same food type and two countries (1)-suggesting high rates of transmission of KpSC within the food sector. Our study provides a novel isolation strategy for KpSC from food matrices and reinforces the view of food as a potential source of KpSC colonization in humans. IMPORTANCE Bacteria of the Klebsiella pneumoniae species complex (KpSC) are ubiquitous, and K. pneumoniae is a leading cause of antibiotic-resistant infections in humans. Despite the urgent public health threat represented by K. pneumoniae, there is a lack of knowledge of the contribution of food sources to colonization and subsequent infection in humans. This is partly due to the absence of standardized methods for characterizing the presence of KpSC in food matrices. Our multicentric study provides and implements a novel isolation strategy for KpSC from food matrices and shows that KpSC members are highly prevalent in salads and chicken meat, reinforcing the view of food as a potential source of KpSC colonization in humans. Despite the large genetic diversity and the low levels of resistance detected, the occurrence of identical genotypes across samples suggests high rates of transmission of KpSC within the food sector, which need to be further explored to define possible control strategies.


Assuntos
Contaminação de Alimentos/estatística & dados numéricos , Klebsiella pneumoniae/isolamento & purificação , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Galinhas , Farmacorresistência Bacteriana Múltipla , Europa (Continente)/epidemiologia , Contaminação de Alimentos/análise , Doenças Transmitidas por Alimentos/microbiologia , Variação Genética , Genótipo , Humanos , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Carne/microbiologia , Testes de Sensibilidade Microbiana , Filogenia , Prevalência , Saladas/microbiologia , beta-Lactamases/genética , beta-Lactamases/metabolismo
8.
Euro Surveill ; 27(49)2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36695439

RESUMO

BackgroundSince 2008, Danish national surveillance of Clostridioides difficile has focused on binary toxin-positive strains in order to monitor epidemic types such as PCR ribotype (RT) 027 and 078. Additional surveillance is needed to provide a more unbiased representation of all strains from the clinical reservoir.AimSetting up a new sentinel surveillance scheme for an improved understanding of type distribution relative to time, geography and epidemiology, here presenting data from 2016 to 2019.MethodsFor 2─4 weeks in spring and autumn each year between 2016 and 2019, all 10 Danish Departments of Clinical Microbiology collected faecal samples containing toxigenic C. difficile. Isolates were typed at the national reference laboratory at Statens Serum Institut. The typing method in 2016-17 used tandem-repeat-sequence typing, while the typing method in 2018-19 was whole genome sequencing.ResultsDuring the study period, the sentinel surveillance scheme included ca 14-15% of all Danish cases of C. difficile infections. Binary toxin-negative strains accounted for 75% and 16 of the 20 most prevalent types. The most common sequence types (ST) were ST2/13 (RT014/020) (19.5%), ST1 (RT027) (10.8%), ST11 (RT078) (6.7%), ST8 (RT002) (6.6%) and ST6 (RT005/117) (5.1%). The data also highlighted geographical differences, mostly related to ST1 and temporal decline of ST1 (p = 0.0008) and the increase of ST103 (p = 0.002), ST17 (p = 0.004) and ST37 (p = 0.003), the latter three binary toxin-negative.ConclusionSentinel surveillance allowed nationwide monitoring of geographical differences and temporal changes in C. difficile infections in Denmark, including emerging types, regardless of binary toxin status.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Humanos , Clostridioides difficile/genética , Clostridioides/genética , Vigilância de Evento Sentinela , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Ribotipagem/métodos , Dinamarca/epidemiologia
9.
Sci Adv ; 7(49): eabj9805, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34851675

RESUMO

The bacterial foodborne pathogen Listeria monocytogenes clonal complex 1 (Lm-CC1) is the most prevalent clonal group associated with human listeriosis and is strongly associated with cattle and dairy products. Here, we analyze 2021 isolates collected from 40 countries, covering Lm-CC1 first isolation to present days, to define its evolutionary history and population dynamics. We show that Lm-CC1 spread worldwide from North America following the Industrial Revolution through two waves of expansion, coinciding with the transatlantic livestock trade in the second half of the 19th century and the rapid growth of cattle farming and food industrialization in the 20th century. In sharp contrast to its global spread over the past century, transmission chains are now mostly local, with limited inter- and intra-country spread. This study provides an unprecedented insight into L. monocytogenes phylogeography and population dynamics and highlights the importance of genome analyses for a better control of pathogen transmission.

10.
Front Microbiol ; 12: 780559, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970240

RESUMO

Phages infecting Campylobacter jejuni are considered a promising intervention strategy at broiler farms, yet phage sensitivity of naturally occurring poultry isolates is not well studied. Here, we investigated phage sensitivity and identified resistance mechanisms of C. jejuni strains originating from Danish broilers belonging to the most prevalent MLST (ST) types. Determining plaque formation of 51 phages belonging to Fletchervirus or Firehammervirus showed that 21 out of 31 C. jejuni strains were susceptible to at least one phage. While C. jejuni ST-21 strains encoded the common phase variable O-methyl phosphoramidate (MeOPN) receptor of the Fletchervirus and were only infected by these phages, ST-45 strains did not encode this receptor and were exclusively infected by Firehammervirus phages. To identify internal phage resistance mechanism in ST-21 strains, we performed comparative genomics of two strains, CAMSA2002 sensitive to almost all Fletchervirus phages and CAMSA2038, resistant to all 51 phages. The strains encoded diverse clustered regularly interspaced short palindromic repeats (CRISPR) spacers but none matched the tested phages. Sequence divergence was also observed in a predicted SspE homolog and putative restriction modification systems including a methyl-specific McrBC endonuclease. Furthermore, when mcrB was deleted, CAMSA2038 became sensitive to 17 out of 43 phages, three being Firehammervirus phages that otherwise did not infect any ST-21 strains. Yet, 16 phages demonstrated significantly lower efficiencies of plating on the mcrB mutant suggesting additional resistance mechanism still restricting phage propagation in CAMSA2038. Thus, our work demonstrates that C. jejuni isolates originating from broilers may have acquired several resistance mechanisms to successfully prevent phage infection in their natural habitat.

11.
Euro Surveill ; 26(22)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34085631

RESUMO

BackgroundCampylobacter is one of the most frequent causes of bacterial gastroenteritis. Campylobacter outbreaks are rarely reported, which could be a reflection of a surveillance without routine molecular typing. We have previously shown that numerous small outbreak-like clusters can be detected when whole genome sequencing (WGS) data of clinical Campylobacter isolates was applied.AimTyping-based surveillance of Campylobacter infections was initiated in 2019 to enable detection of large clusters of clinical isolates and to match them to concurrent retail chicken isolates in order to react on ongoing outbreaks.MethodsWe performed WGS continuously on isolates from cases (n = 701) and chicken meat (n = 164) throughout 2019. Core genome multilocus sequence typing was used to detect clusters of clinical isolates and match them to isolates from chicken meat.ResultsSeventy-two clusters were detected, 58 small clusters (2-4 cases) and 14 large clusters (5-91 cases). One third of the clinical isolates matched isolates from chicken meat. One large cluster persisted throughout the whole year and represented 12% of all studied Campylobacter cases. This cluster type was detected in several chicken samples and was traced back to one slaughterhouse, where interventions were implemented to control the outbreak.ConclusionOur WGS-based surveillance has contributed to an improved understanding of the dynamics of the occurrence of Campylobacter strains in chicken meat and the correlation to clusters of human cases.


Assuntos
Infecções por Campylobacter , Campylobacter jejuni , Animais , Infecções por Campylobacter/diagnóstico , Infecções por Campylobacter/epidemiologia , Campylobacter jejuni/genética , Galinhas , Dinamarca/epidemiologia , Surtos de Doenças , Genoma Bacteriano , Humanos , Tipagem de Sequências Multilocus , Sequenciamento Completo do Genoma
12.
Zoonoses Public Health ; 68(6): 638-649, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34041858

RESUMO

Campylobacter jejuni is the leading cause of bacterial gastroenteritis globally, and infections are often transmitted through consumption of raw or undercooked poultry. Campylobacter jejuni ST50 is among the top ten sequence types (STs) reported in the collected isolates listed at PubMLST records from poultry, food and clinical sources for Asia, Europe, North America, Oceania and South America. This study was designed to determine the most commonly reported C. jejuni STs globally using the PubMLST database and assess similarities between genomes of C. jejuni ST50 isolates from geographically distinct locations. To gain a better understanding of C. jejuni diversity, we compared draft genome sequences of 182 ST50 isolates recovered from retail or caecal poultry samples in Oceania, Europe and North America that were collected over a period of 9 years (2010 to 2018). Overall, phylogenetic analysis revealed that isolates from geographically distinct locations tended to cluster based on the continent where the sample was collected. Among ST50 isolates from Europe and North America, we identified resistance determinants associated with phenotypic resistance to beta-lactams (EU: 55%; GB: 43.1%), tetracyclines (CA: 77.3%; EU: 37.5%; GB: 9.8%; US: 43.5%) and fluoroquinolones (EU: 60.0%; GB: 15.7%); no resistance determinants were identified in isolates from Australia. In general, the majority of the virulence genes, with rare exceptions such as wlaN, cj1138, hddA and rfbC, were evenly distributed throughout the genomes of all ST50 isolates in this study. Genomic-based characterization of C. jejuni ST50 isolates from poultry on three continents highlighted that geographically distinct isolates have evolved independently but only represent a glimpse into the diversity of C. jejuni.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter jejuni/genética , Genômica/métodos , Doenças das Aves Domésticas/microbiologia , Aves Domésticas/microbiologia , Animais , Antibacterianos/farmacologia , Austrália/epidemiologia , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Europa (Continente)/epidemiologia , Genoma Bacteriano , Funções Verossimilhança , América do Norte/epidemiologia , Filogenia , Doenças das Aves Domésticas/epidemiologia
13.
Eur J Clin Microbiol Infect Dis ; 40(4): 673-682, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32974772

RESUMO

Campylobacter jejuni is recognised as the leading cause of bacterial gastroenteritis in industrialised countries. Although the majority of Campylobacter infections are self-limiting, antimicrobial treatment is necessary in severe cases. Therefore, the development of antimicrobial resistance (AMR) in Campylobacter is a growing public health challenge and surveillance of AMR is important for bacterial disease control. The aim of this study was to predict antimicrobial resistance in C. jejuni from whole-genome sequencing data. A total of 516 clinical C. jejuni isolates collected between 2014 and 2017 were subjected to WGS. Resistance phenotypes were determined by standard broth dilution, categorising isolates as either susceptible or resistant based on epidemiological cutoffs for six antimicrobials: ciprofloxacin, nalidixic acid, erythromycin, gentamicin, streptomycin, and tetracycline. Resistance genotypes were identified using an in-house database containing reference genes with known point mutations and the presence of resistance genes was determined using the ResFinder database and four bioinformatical methods (modified KMA, ABRicate, ARIBA, and ResFinder Batch Upload). We identified seven resistance genes including tet(O), tet(O/32/O), ant(6)-Ia, aph(2″)-If, blaOXA, aph(3')-III, and cat as well as mutations in three genes: gyrA, 23S rRNA, and rpsL. There was a high correlation between phenotypic resistance and the presence of known resistance genes and/or point mutations. A correlation above 98% was seen for all antimicrobials except streptomycin with a correlation of 92%. In conclusion, we found that WGS can predict antimicrobial resistance with a high degree of accuracy and have the potential to be a powerful tool for AMR surveillance.


Assuntos
Antibacterianos/farmacologia , Campylobacter jejuni/efeitos dos fármacos , Farmacorresistência Bacteriana , Genoma Bacteriano , Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Sequenciamento Completo do Genoma
14.
Emerg Infect Dis ; 26(3): 523-532, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32091364

RESUMO

In industrialized countries, the leading cause of bacterial gastroenteritis is Campylobacter jejuni. However, outbreaks are rarely reported, which may reflect limitations of surveillance, for which molecular typing is not routinely performed. To determine the frequency of genetic clusters among patients and to find links to concurrent isolates from poultry meat, broiler chickens, cattle, pigs, and dogs, we performed whole-genome sequencing on 1,509 C. jejuni isolates from 774 patients and 735 food or animal sources in Denmark during 2015-2017. We found numerous clusters; 366/774 (47.3%) clinical isolates formed 104 clusters of >2 isolates. A total of 41 patient clusters representing 199/366 (54%) patients matched a potential source, primarily domestic chickens/broilers. This study revealed serial outbreaks and numerous matches to concurrent food and animal isolates and highlighted the potential of whole-genome sequencing for improving routine surveillance of C. jejuni by enhancing outbreak detection, source tracing, and potentially prevention of human infections.


Assuntos
Infecções por Campylobacter/epidemiologia , Campylobacter jejuni/isolamento & purificação , Surtos de Doenças , Doenças Transmitidas por Alimentos/epidemiologia , Gastroenterite/epidemiologia , Animais , Infecções por Campylobacter/etiologia , Campylobacter jejuni/genética , Bovinos , Galinhas , Dinamarca/epidemiologia , Cães , Feminino , Doenças Transmitidas por Alimentos/etiologia , Gastroenterite/etiologia , Humanos , Masculino , Sequenciamento Completo do Genoma
15.
Front Microbiol ; 11: 1205, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34354676

RESUMO

Salmonella enterica subspecies enterica serovar Typhimurium and its monophasic variant are among the most common Salmonella serovars associated with human salmonellosis each year. Related infections are often due to consumption of contaminated meat of pig, cattle, and poultry origin. In order to evaluate novel microbial subtyping methods for source attribution, an approach based on weighted networks was applied on 141 human and 210 food and animal isolates of pigs, broilers, layers, ducks, and cattle collected in Denmark from 2013 to 2014. A whole-genome SNP calling was performed along with cgMLST and wgMLST. Based on these genomic input data, pairwise distance matrices were built and used as input for construction of a weighted network where nodes represent genomes and links to distances. Analyzing food and animal Typhimurium genomes, the coherence of source clustering ranged from 89 to 90% for animal source, from 84 to 85% for country, and from 63 to 65% for year of isolation and was equal to 82% for serotype, suggesting animal source as the first driver of clustering formation. Adding human isolate genomes to the network, a percentage between 93.6 and 97.2% clustered with the existing component and only a percentage between 2.8 and 6.4% appeared as not attributed to any animal sources. The majority of human genomes were attributed to pigs with probabilities ranging from 83.9 to 84.5%, followed by broilers, ducks, cattle, and layers in descending order. In conclusion, a weighted network approach based on pairwise SNPs, cgMLST, and wgMLST matrices showed promising results for source attribution studies.

16.
BMC Genomics ; 20(1): 870, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730461

RESUMO

BACKGROUND: Salmonella Infantis (S. Infantis) is one of the most frequent Salmonella serovars isolated from human cases of salmonellosis and the most detected serovar from animal and food sources in Europe. The serovar is commonly associated with poultry and there is increasing concern over multidrug resistant clones spreading worldwide, as the dominating clones are characterized by presence of large plasmids carrying multiple resistance genes. Increasing the knowledge of the S. Infantis population and evolution is important for understanding and preventing further spread. In this study, we analysed a collection of strains representing different decades, sources and geographic locations. We analysed the population structure and the accessory genome, in particular we identified prophages with a view to understand the role of prophages in relation to the evolution of this serovar. RESULTS: We sequenced a global collection of 100 S. Infantis strains. A core-genome SNP analysis separated five strains in e-Burst Group (eBG) 297 with a long branch. The remaining strains, all in eBG31, were divided into three lineages that were estimated to have separated approximately 150 years ago. One lineage contained the vast majority of strains. In five of six clusters, no obvious correlation with source or geographical locations was seen. However, one cluster contained mostly strains from human and avian sources, indicating a clone with preference for these sources. The majority of strains within this cluster harboured a pESI-like plasmid with multiple resistance genes. Another lineage contained three genetic clusters with more rarely isolated strains of mainly animal origin, possibly less sampled or less infectious clones. Conserved prophages were identified in all strains, likely representing bacteriophages which integrated into the chromosome of a common ancestor to S. Infantis. We also saw that some prophages were specific to clusters and were probably introduced when the clusters were formed. CONCLUSIONS: This study analysed a global S. Infantis population and described its genetic structure. We hypothesize that the population has evolved in three separate lineages, with one more successfully emerging lineage. We furthermore detected conserved prophages present in the entire population and cluster specific prophages, which probably shaped the population structure.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Genoma Bacteriano , Filogenia , Polimorfismo de Nucleotídeo Único , Salmonella enterica/genética , Animais , Antibacterianos/farmacologia , Ásia/epidemiologia , Galinhas , Europa (Continente)/epidemiologia , Humanos , Família Multigênica , Filogeografia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/microbiologia , Prófagos , Salmonelose Animal/epidemiologia , Salmonelose Animal/microbiologia , Salmonella enterica/classificação , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/isolamento & purificação , Estados Unidos/epidemiologia , Sequenciamento Completo do Genoma
17.
Microb Genom ; 5(2)2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30775964

RESUMO

We present the LiSEQ (Listeria SEQuencing) project, funded by the European Food Safety Agency (EFSA) to compare Listeria monocytogenes isolates collected in the European Union from ready-to-eat foods, compartments along the food chain (e.g. food-producing animals, food-processing environments) and humans. In this article, we report the molecular characterization of a selection of this data set employing whole-genome sequencing analysis. We present an overview of the strain diversity observed in different sampled sources, and characterize the isolates based on their virulence and resistance profile. We integrate into our analysis the global L. monocytogenes genome collection described by Moura and colleagues in 2016 to assess the representativeness of the LiSEQ collection in the context of known L. monocytogenes strain diversity.


Assuntos
Laticínios/microbiologia , Produtos Pesqueiros/microbiologia , Listeria monocytogenes/classificação , Listeriose/microbiologia , Produtos da Carne/microbiologia , Animais , Estudos Transversais , Farmacorresistência Bacteriana/genética , Europa (Continente) , Manipulação de Alimentos , Microbiologia de Alimentos , Variação Genética , Humanos , Listeria monocytogenes/genética , Listeria monocytogenes/isolamento & purificação , Virulência/genética , Sequenciamento Completo do Genoma
18.
Clin Epidemiol ; 10: 1695-1707, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538574

RESUMO

BACKGROUND: Each year more than 4,000 cases of campylobacteriosis are reported in Denmark, making it the most common bacterial gastrointestinal infection. Here we describe a case-control study to identify sources of infection with a focus on environmental factors. METHODS: From January to December 2016, we conducted a prospective case-control study among Danish persons aged 1-30 years. Participants were invited by letter to complete an online questionnaire. Crude and adjusted ORs were calculated and final parsimonious multivariate models developed using logistic regression. RESULTS: The study recruited 1366 cases and 4,418 controls, of whom 65% and 66%, respectively, completed the questionnaire. A multivariate model for domestically acquired cases showed, among others, increased risk of infection with bathing in fresh water (OR=5.1), contact to beach sand (OR=1.8), owning a pet dog with diarrhea (OR=4.6), and eating minced beef (OR=2.6) or chicken (OR=2.5). The model for children highlighted similar risk factors but also included bathing in a paddling pool (OR=13.6) and eating fresh strawberries (OR=5.3). A separate analysis for persons reporting foreign travel showed increased infection risk when traveling to Asia, Africa, or Turkey and that eating from street kitchens and having contact to water during traveling were also risk factors. CONCLUSION: Environmental factors and animal contact account for a sizeable proportion of domestic Campylobacter infections in the age group studied. The study also re-confirmed handling/consumption of chicken as an important risk factor while highlighting minced beef as a potential new risk factor. Overall, these results contribute to a better understanding of the transmission dynamics of Campylobacter and will be used to improve national guidelines for prevention of infection.

19.
Eur J Paediatr Neurol ; 22(5): 774-781, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29871800

RESUMO

OBJECTIVE: To explore paediatricians' attitudes to and treatment practice for children with functional seizures (FS). METHODS: In a nationwide survey, all 64 Danish neuro-paediatricians and social paediatricians were invited to complete a structured questionnaire encompassing FS-related issues that included beliefs and attitudes about aetiology and diagnostic assessment, current strategies for management, experienced need for clinical guidelines and better treatment options. RESULTS: A total of 61 paediatricians (95%) participated in the study. Nearly half (46%) had seen more than 30 children with FS during their career. Most (65%) believed in a primarily psychogenic aetiology. More than half (57%) stated that they could make the diagnosis by solely observing a seizure, and 18% indicated the children faked their symptoms. The paediatricians' responses to these issues did not significantly vary according to their level of clinical experience. Furthermore, the majority (78%) expressed a need for clinical guidelines, and only 13% rated existing treatment options as sufficient. Collaborative care between different specialties or management in a child and adolescent mental health services (CAMHS) setting was seen as the best model for treatment. However, only 23% reported often referring these children to CAMHS after making the diagnosis. CONCLUSION: The findings suggest that introduction of clinical guidelines in this area is highly needed. Such guidelines could promote more formal training of paediatricians in understanding and assessing FS and increased collaboration between paediatrics and CAMHS regarding care for children with this challenging and potentially costly and disabling disorder.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pediatras , Convulsões/diagnóstico , Convulsões/terapia , Adolescente , Criança , Feminino , Humanos , Masculino , Inquéritos e Questionários
20.
Euro Surveill ; 22(50)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29258647

RESUMO

In August 2017, an outbreak of six listeriosis cases in Denmark was traced to cold-smoked salmon, using epidemiological investigations and whole-genome sequencing (WGS) analyses. Exchange of genome sequences allowed identification in France of a food isolate from a salmon-derived product and a human isolate from 2016 within the same cgMLST cluster as the Danish isolates (L2-SL8-ST8-CT771). The salmon product came from a third European Union country. WGS can rapidly link human cases and food isolates across Europe.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Doenças Transmitidas por Alimentos , Genoma Bacteriano/genética , Listeria monocytogenes/genética , Listeriose/epidemiologia , Salmão/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Dinamarca/epidemiologia , Emigração e Imigração , Feminino , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , França/epidemiologia , Humanos , Listeria monocytogenes/isolamento & purificação , Listeriose/diagnóstico , Listeriose/microbiologia , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
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