Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 41
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Euro Surveill ; 29(16)2024 Apr.
Article in English | MEDLINE | ID: mdl-38639094

ABSTRACT

In 2023, an increase of OXA-48-producing Klebsiella pneumoniae was noticed by the Lithuanian National Public Health Surveillance Laboratory. Whole genome sequencing (WGS) of 106 OXA-48-producing K. pneumoniae isolates revealed three distinct clusters of carbapenemase-producing K. pneumoniae high-risk clones, including sequence type (ST) 45 (n = 35 isolates), ST392 (n = 32) and ST395 (n = 28), involving six, six and nine hospitals in different regions, respectively. These results enabled targeted investigation and control, and underscore the value of national WGS-based surveillance for antimicrobial resistance.


Subject(s)
Klebsiella Infections , Klebsiella pneumoniae , Humans , Klebsiella pneumoniae/genetics , Lithuania/epidemiology , Multilocus Sequence Typing , Klebsiella Infections/epidemiology , Klebsiella Infections/drug therapy , beta-Lactamases/genetics , Bacterial Proteins/genetics , Hospitals , Disease Outbreaks , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use
2.
Euro Surveill ; 28(47)2023 11.
Article in English | MEDLINE | ID: mdl-37997662

ABSTRACT

BackgroundPreliminary unpublished results of the survey of carbapenem- and/or colistin-resistant Enterobacterales (CCRE survey) showed the expansion of carbapenemase-producing Klebsiella pneumoniae (CPKP) sequence type (ST) 39 in 12 of 15 participating Greek hospitals in 2019.AimWe conducted a rapid survey to determine the extent of spread of CPKP high-risk clones in Greek hospitals in 2022 and compare the distribution of circulating CPKP clones in these hospitals since 2013.MethodsWe analysed whole genome sequences and epidemiological data of 310 K. pneumoniae isolates that were carbapenem-resistant or 'susceptible, increased exposure' from Greek hospitals that participated in the European survey of carbapenemase-producing Enterobacteriaceae (EuSCAPE, 2013-2014), in the CCRE survey (2019) and in a national follow-up survey (2022) including, for the latter, an estimation of transmission events.ResultsFive K. pneumoniae STs including ST258/512 (n = 101 isolates), ST11 (n = 93), ST39 (n = 56), ST147 (n = 21) and ST323 (n = 13) accounted for more than 90% of CPKP isolates in the dataset. While ST11, ST147 and ST258/512 have been detected in participating hospitals since 2013 and 2014, KPC-2-producing ST39 and ST323 emerged in 2019 and 2022, respectively. Based on the defined genetic relatedness cut-off, 44 within-hospital transmission events were identified in the 2022 survey dataset, with 12 of 15 participating hospitals having at least one within-hospital transmission event.ConclusionThe recent emergence and rapid spread of new high-risk K. pneumoniae clones in the Greek healthcare system related to within-hospital transmission is of concern and highlights the need for molecular surveillance and enhanced infection prevention and control measures.


Subject(s)
Carbapenem-Resistant Enterobacteriaceae , Klebsiella Infections , Humans , Klebsiella pneumoniae/genetics , Carbapenem-Resistant Enterobacteriaceae/genetics , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Greece/epidemiology , Klebsiella Infections/epidemiology , Klebsiella Infections/drug therapy , Multilocus Sequence Typing , beta-Lactamases/genetics , Bacterial Proteins/genetics , Carbapenems/pharmacology , Hospitals , Clone Cells , Microbial Sensitivity Tests
3.
Euro Surveill ; 28(19)2023 05.
Article in English | MEDLINE | ID: mdl-37166762

ABSTRACT

Whole genome sequencing data of 874 Escherichia coli isolates carrying bla NDM-5 from 13 European Union/European Economic Area countries between 2012 and June 2022 showed the predominance of sequence types ST167, ST405, ST410, ST361 and ST648, and an increasing frequency of detection. Nearly a third (30.6%) of these isolates were associated with infections and more than half (58.2%) were predicted to be multidrug-resistant. Further spread of E. coli carrying bla NDM-5 would leave limited treatment options for serious E. coli infections.


Subject(s)
Escherichia coli Infections , Escherichia coli , Humans , beta-Lactamases/genetics , Drug Resistance, Multiple, Bacterial/genetics , Escherichia coli/genetics , Escherichia coli/isolation & purification , Escherichia coli Infections/drug therapy , Escherichia coli Infections/epidemiology , European Union , Microbial Sensitivity Tests , Europe/epidemiology
4.
Euro Surveill ; 27(15)2022 04.
Article in English | MEDLINE | ID: mdl-35426364

ABSTRACT

In the WHO European Region, COVID-19 non-pharmaceutical interventions continued slowing influenza circulation in the 2021/22 season, with reduced characterisation data. A(H3) predominated and, in some countries, co-circulated with A(H1)pdm09 and B/Victoria viruses. No B/Yamagata virus detections were confirmed. Substantial proportions of characterised circulating virus subtypes or lineages differed antigenically from their respective northern hemisphere vaccine components. Appropriate levels of influenza virus characterisations should be maintained until the season end and in future seasons, when surveillance is adapted to integrate SARS-CoV-2.


Subject(s)
COVID-19 , Influenza Vaccines , Influenza, Human , Humans , Influenza A Virus, H3N2 Subtype/genetics , Influenza B virus/genetics , Influenza, Human/epidemiology , Influenza, Human/prevention & control , SARS-CoV-2 , Seasons , World Health Organization
5.
Euro Surveill ; 27(17)2022 04.
Article in English | MEDLINE | ID: mdl-35485272

ABSTRACT

Many countries, including some within the EU/EEA, are in the process of transitioning from the acute pandemic phase. During this transition, it is crucial that countries' strategies and activities remain guided by clear COVID-19 control objectives, which increasingly will focus on preventing and managing severe outcomes. Therefore, attention must be given to the groups that are particularly vulnerable to severe outcomes of SARS-CoV-2 infection, including individuals in congregate and healthcare settings. In this phase of pandemic management, a strong focus must remain on transitioning testing approaches and systems for targeted surveillance of COVID-19, capitalising on and strengthening existing systems for respiratory virus surveillance. Furthermore, it will be crucial to focus on lessons learned from the pandemic to enhance preparedness and to enact robust systems for the preparedness, detection, rapid investigation and assessment of new and emerging SARS-CoV-2 variants. Filling existing knowledge gaps, including behavioural insights, can help guide the response to future resurgences of SARS-CoV-2 and/or the emergence of other pandemics. Finally, 'vaccine agility' will be needed to respond to changes in people's behaviours, changes in the virus, and changes in population immunity, all the while addressing issues of global health equity.


Subject(s)
COVID-19 , Humans , Pandemics/prevention & control , Public Health , SARS-CoV-2
6.
Article in English | MEDLINE | ID: mdl-32122893

ABSTRACT

In this retrospective study, whole-genome sequencing (WGS) data generated on an Ion Torrent platform was used to predict phenotypic drug resistance profiles for first- and second-line drugs among Swedish clinical Mycobacterium tuberculosis isolates from 2016 to 2018. The accuracy was ∼99% for all first-line drugs and 100% for four second-line drugs. Our analysis supports the introduction of WGS into routine diagnostics, which might, at least in Sweden, replace phenotypic drug susceptibility testing in the future.


Subject(s)
Drug Resistance, Multiple, Bacterial/drug effects , Drug Resistance, Multiple, Bacterial/genetics , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/genetics , Tuberculosis/microbiology , Whole Genome Sequencing , Humans , Sweden , Tuberculosis, Multidrug-Resistant/drug therapy
7.
Euro Surveill ; 25(46)2020 11.
Article in English | MEDLINE | ID: mdl-33213683

ABSTRACT

The COVID-19 pandemic negatively impacted the 2019/20 WHO European Region influenza surveillance. Compared with previous 4-year averages, antigenic and genetic characterisations decreased by 17% (3,140 vs 2,601) and 24% (4,474 vs 3,403). Of subtyped influenza A viruses, 56% (26,477/47,357) were A(H1)pdm09, 44% (20,880/47,357) A(H3). Of characterised B viruses, 98% (4,585/4,679) were B/Victoria. Considerable numbers of viruses antigenically differed from northern hemisphere vaccine components. In 2020/21, maintaining influenza virological surveillance, while supporting SARS-CoV-2 surveillance is crucial.


Subject(s)
Coronavirus Infections/epidemiology , Disease Notification/statistics & numerical data , Epidemiological Monitoring , Influenza A virus/isolation & purification , Influenza B virus/isolation & purification , Influenza, Human/epidemiology , Influenza, Human/virology , Antigens, Viral/genetics , Betacoronavirus , COVID-19 , Humans , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza A Virus, H3N2 Subtype/genetics , Influenza A Virus, H3N2 Subtype/isolation & purification , Influenza A virus/genetics , Influenza B virus/genetics , Pandemics , Pneumonia, Viral , Population Surveillance , RNA, Viral/genetics , SARS-CoV-2 , Sequence Analysis, DNA
8.
Euro Surveill ; 25(32)2020 Aug.
Article in English | MEDLINE | ID: mdl-32794443

ABSTRACT

We show the distribution of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three genomic nomenclature systems to all sequence data from the World Health Organization European Region available until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation, compare the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2.


Subject(s)
Betacoronavirus/genetics , Coronavirus Infections/epidemiology , Coronavirus/genetics , Genome, Viral/genetics , Pandemics , Pneumonia, Viral/epidemiology , RNA, Viral/analysis , RNA-Dependent RNA Polymerase/genetics , Base Sequence , Betacoronavirus/pathogenicity , COVID-19 , Coronavirus/isolation & purification , Coronavirus Infections/virology , Europe/epidemiology , Humans , Phylogeography , Pneumonia, Viral/virology , RNA, Viral/genetics , SARS-CoV-2 , Severe Acute Respiratory Syndrome , Spatio-Temporal Analysis , World Health Organization
9.
Euro Surveill ; 25(20)2020 05.
Article in English | MEDLINE | ID: mdl-32458791

ABSTRACT

Analysis of sequencing data for 143 blaNDM-1- and blaOXA-48-positive Klebsiella pneumoniae isolates from 13 European national collections and the public domain resulted in the identification of 15 previously undetected multi-country transmission clusters. For 10 clusters, cases had prior travel/hospitalisation history in countries outside of the European Union including Egypt, Iran, Morocco, Russia, Serbia, Tunisia and Turkey. These findings highlight the benefit of European whole genome sequencing-based surveillance and data sharing for control of antimicrobial resistance.


Subject(s)
Bacterial Proteins/genetics , Carbapenem-Resistant Enterobacteriaceae/genetics , Carbapenem-Resistant Enterobacteriaceae/isolation & purification , Disease Outbreaks , Klebsiella Infections/epidemiology , Klebsiella pneumoniae/genetics , Whole Genome Sequencing/methods , beta-Lactamases/genetics , Anti-Bacterial Agents/therapeutic use , Carbapenem-Resistant Enterobacteriaceae/drug effects , Carbapenems/therapeutic use , Emigration and Immigration , Humans , Klebsiella Infections/drug therapy , Klebsiella Infections/microbiology , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/isolation & purification , Microbial Sensitivity Tests/methods
10.
J Clin Microbiol ; 55(6): 1920-1927, 2017 06.
Article in English | MEDLINE | ID: mdl-28404681

ABSTRACT

Pyrazinamide (PZA) is a key component for the effective treatment of drug-susceptible and PZA-susceptible multidrug-resistant (MDRPZA-S) tuberculosis (TB). pncA gene mutations are usually detected in a clear majority (>90%) of PZA-resistant strains but obviously not in all. Rapid and reliable PZA drug susceptibility testing (DST) is critical whenever PZA is to be used in a treatment regimen, not least for the treatment of MDRPZA-S TB. In this study, we selected 26 PZA-resistant isolates reported to carry a wild-type pncA gene. To confirm resistance, susceptibility testing was repeated using 100 mg/liter and 200 mg/liter PZA for all the 26 isolates and Sanger sequencing was repeated on the 18 isolates that remained PZA resistant. Apart from the eight isolates initially misclassified as PZA resistant, the retests identified three factors responsible for the phenotype-genotype discrepancy: panD or rpsA mutations identified by whole-genome sequencing (WGS) (n = 7), heteroresistance (n = 8), and mixed populations with Mycobacterium avium (n = 3). Additionally, we performed WGS on 400 PZA-susceptible isolates and 15 consecutive MDRPZA-R clinical isolates. Of the 400 PZA-susceptible isolates, only 1 harbored a nonsynonymous pncA mutation (Thr87Met), whereas a nonsynonymous rpsA mutation was found in 17 isolates. None of these isolates carried a nonsynonymous panD mutation, while all 15 of the MDRPZA-R isolates harbored a nonsynonymous pncA mutation. Our findings indicate that it is necessary to consider the occurrence of panD mutations in PZA-resistant isolates, as well as heteroresistance, for the development and evaluation of new molecular techniques to ensure high-quality DST performance. The identification of nonsynonymous rpsA mutations in both PZA-susceptible and PZA-resistant isolates also implies that further studies are needed in order to determine the role of rpsA in PZA resistance.


Subject(s)
Amidohydrolases/genetics , Antitubercular Agents/pharmacology , Drug Resistance, Bacterial , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/genetics , Pyrazinamide/pharmacology , Coinfection/microbiology , Genes, Bacterial , Humans , Microbial Sensitivity Tests , Mutation , Mycobacterium avium/isolation & purification , Sequence Analysis, DNA , Tuberculosis/microbiology , Whole Genome Sequencing
11.
J Antimicrob Chemother ; 72(8): 2184-2190, 2017 08 01.
Article in English | MEDLINE | ID: mdl-28541565

ABSTRACT

Objectives: To describe the changing epidemiology of vancomycin-resistant Enterococcus faecium and Enterococcus faecalis in clinical samples in Denmark 2005-15 according to species and van type, and, furthermore, to investigate the genetic relatedness of the clinical E. faecium isolates from 2015. Methods: During 2005-14, all clinical VRE isolates were tested for the presence of vanA/B/C genes by PCR. In 2015, all clinical VRE isolates were whole-genome sequenced. From the WGS data, the presence of van genes and MLST STs were extracted in silico . Core-genome MLST (cgMLST) analysis was performed for the vancomycin-resistant E. faecium isolates. Results: During 2005-15, 1043 vanA E. faecium , 25 vanB E. faecium , 4 vanA E. faecalis and 28 vanB E. faecalis were detected. The number of VRE was <50 isolates/year until 2012 to > 200 isolates/year in 2013-15. In 2015, 368 vanA E. faecium and 1 vanB E. faecium were detected along with 1 vanA E. faecalis and 1 vanB E. faecalis . cgMLST subdivided the 368 vanA E. faecium isolates into 33 cluster types (CTs), whereas the vanB E. faecium isolate belonged to a different CT. ST203-CT859 was most prevalent (51%), followed by ST80-CT14 (22%), ST117-CT24 (6%), ST80-CT866 (4%) and ST80-CT860 (2%). Comparison with the cgMLST.org database, previous studies and personal communications with neighbouring countries revealed that the novel cluster ST203-CT859 emerged in December 2014 and spread to the south of Sweden and the Faroe Islands during 2015. Conclusions: VRE increased in Denmark during 2005-15 due to the emergence of several vanA E. faecium clones.


Subject(s)
Bacterial Proteins/genetics , Carbon-Oxygen Ligases/genetics , Enterococcus faecium/genetics , Gram-Positive Bacterial Infections/epidemiology , Gram-Positive Bacterial Infections/microbiology , Vancomycin-Resistant Enterococci/genetics , DNA, Bacterial/genetics , Denmark/epidemiology , Enterococcus faecium/isolation & purification , Humans , Multilocus Sequence Typing , Polymerase Chain Reaction , Sequence Analysis, DNA , Vancomycin-Resistant Enterococci/isolation & purification
12.
BMC Infect Dis ; 17(1): 230, 2017 03 24.
Article in English | MEDLINE | ID: mdl-28340558

ABSTRACT

BACKGROUND: Brucellosis is a zoonosis that occurs worldwide. The disease has been completely eradicated in livestock in Sweden in 1994, and all cases of confirmed human brucellosis are imported into Sweden from other countries. However, due to an increase in the number of refugees and asylum seekers from the middle-east to Sweden, there is a need to improve the current diagnostic methodology for Brucella melitensis. Whilst culture of Brucella species can be used as a diagnostic tool, real-time PCR approaches provide a much faster result. The aim of this study was to set up a species-specific real-time PCR for the detection of all biovars of Brucella melitensis, which could be used routinely in diagnostic laboratories. METHODS: A Brucella melitensis real-time PCR assay was designed using all available genomes in the public database of Brucella (N = 96) including all complete genomes of Brucella melitensis (N = 17). The assay was validated with a collection of 37 Brucella species reference strains, 120 Brucella melitensis human clinical isolates, and 45 clinically relevant non-Brucella melitensis strains. RESULTS: In this study we developed a single real-time PCR for the specific detection of all biovars of Brucella melitensis. CONCLUSIONS: This new real-time PCR method shows a high specificity (100%) and a high sensitivity (1.25 GE/µl) and has been implemented in the laboratories of four governmental authorities across Sweden.


Subject(s)
Brucella melitensis/genetics , Brucellosis/diagnosis , Brucellosis/microbiology , Molecular Typing/methods , Real-Time Polymerase Chain Reaction/methods , Humans
13.
Euro Surveill ; 22(22)2017 Jun 01.
Article in English | MEDLINE | ID: mdl-28602163

ABSTRACT

A food-borne outbreak of gastroenteritis with more than 650 suspected cases occurred in April 2016 in Sollentuna, Sweden. It originated in a school kitchen serving a total of 2,700 meals daily. Initial microbiological testing (for Campylobacter, Salmonella, Shigella, Yersinia, Giardia, Cryptosporidium, Entamoeba histolytica, adeno-, astro-, noro-, rota- and sapovirus) of stool samples from 15 symptomatic cases was negative, despite a clinical presentation suggestive of calicivirus. Analyses of the findings from both the Sollentuna municipality environmental team and a web-based questionnaire suggested that the source of the outbreak was the salad buffet served on 20 April, although no specific food item could be identified. Subsequent electron microscopic examination of stool samples followed by whole genome sequencing revealed a variant of sapovirus genogroup V. The virus was not detected using standard PCR screening. This paper describes the epidemiological outbreak investigation and findings leading to the discovery.


Subject(s)
Caliciviridae Infections/diagnosis , Disease Outbreaks , Foodborne Diseases/epidemiology , Gastroenteritis/diagnosis , Sapovirus/isolation & purification , Caliciviridae Infections/epidemiology , Caliciviridae Infections/virology , Feces/virology , Gastroenteritis/epidemiology , Gastroenteritis/virology , Humans , Male , Reverse Transcriptase Polymerase Chain Reaction , Sapovirus/classification , Sapovirus/genetics , Schools , Sweden/epidemiology
14.
J Clin Microbiol ; 54(5): 1335-9, 2016 05.
Article in English | MEDLINE | ID: mdl-26962084

ABSTRACT

Rodent-borne hantaviruses cause two severe acute diseases: hemorrhagic fever with renal syndrome (HFRS) in Eurasia, and hantavirus pulmonary syndrome (HPS; also called hantavirus cardiopulmonary syndrome [HCPS]) in the Americas. Puumala virus (PUUV) is the most common causative agent of HFRS in Europe. Current routine diagnostic methods are based on serological analyses and can yield inconclusive results. Hantavirus-infected patients are viremic during the early phase of disease; therefore, detection of viral RNA genomes can be a valuable complement to existing serological methods. However, the high genomic sequence diversity of PUUV has hampered the development of molecular diagnostics, and currently no real-time reverse transcription-quantitative (RT)-PCR assay is available for routine diagnosis of HFRS. Here, we present a novel PUUV RT-PCR assay. The assay was validated for routine diagnosis of HFRS on samples collected in Sweden during the winter season from 2013 to 2014. The assay allowed detection of PUUV RNA in 98.7% of confirmed clinical HFRS samples collected within 8 days after symptomatic onset. In summary, this study shows that real-time RT-PCR can be a reliable alternative to serological tests during the early phase of HFRS.


Subject(s)
Hemorrhagic Fever with Renal Syndrome/diagnosis , Molecular Diagnostic Techniques/methods , Puumala virus/isolation & purification , Real-Time Polymerase Chain Reaction/methods , Reverse Transcriptase Polymerase Chain Reaction/methods , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Sweden
15.
Int J Syst Evol Microbiol ; 65(Pt 2): 598-603, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25406235

ABSTRACT

Fourteen isolates of an unknown species identified as belonging to the genus Legionella by selective growth on BCYE agar were isolated from the biopurification systems of three different wood processing plants. The mip gene sequence of all 14 isolates was identical and a close match alignment revealed 86 % sequence similarity with Legionella pneumophila serogroup 8. The whole genome of isolate LEGN(T) was sequenced, and a phylogenetic tree based on the alignment of 16S rRNA, mip, rpoB, rnpB and the 23S-5S intergenic region clustered LEGN(T) with L. pneumophila ATCC 33152(T). Analysis of virulence factors showed that strain LEGN(T) carries the majority of known L. pneumophila virulence factors. An amoeba infection assay performed to assess the pathogenicity of strain LEGN(T) towards Acanthamoeba castellanii showed that it can establish a replication vacuole in A. castellanii but does not significantly affect replication of amoebae. Taken together, the results confirm that strain LEGN(T) represents a novel species of the genus Legionella, for which the name Legionella norrlandica sp. nov. is proposed. The type strain is LEGN(T) ( = ATCC BAA-2678(T) = CCUG 65936(T)).


Subject(s)
Legionella/classification , Phylogeny , Wood/microbiology , Amoeba/microbiology , DNA, Bacterial/genetics , DNA, Intergenic/genetics , Genes, Bacterial , Legionella/genetics , Legionella/isolation & purification , Molecular Sequence Data , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Virulence Factors/genetics
16.
BMC Infect Dis ; 15: 493, 2015 Nov 02.
Article in English | MEDLINE | ID: mdl-26527283

ABSTRACT

BACKGROUND: Dengue is one of the leading causes of morbidity in tropical and subtropical regions and infection with any of the four dengue virus serotypes (DENV1-4) result in a wide range of clinical manifestations. Given the geographic expansion of DENV1-4, assays for serotyping are needed to be able to perform surveillance and epidemiological studies. In this study, we describe the design and validation of one-step real-time serotype-specific DENV RT-PCR assays. METHODS: The DENV1, DENV2, DENV3, and DENV4 RT-PCR assays were designed using all available whole genome DENV sequences in the NCBI nucleotide collection. Because of the high mutation rates of RNA viruses, the assays were performed in singleplex format to enable quick modifications to the primer and probe sequences when new genetic variants emerge. The analytical performance of the RT-PCR assays were evaluated using in vitro transcribed RNA and their specificity was determined by testing 24 DENV isolates, external DENV control panels and RNA preparation of non-DENV flaviviruses and non-dengue clinical samples. Additionally, the clinical performance of the serotype-specific DENV RT-PCR were compared to that of the CDC DENV-1-4 RT-PCR using 85 clinical samples collected from patients presenting with acute dengue. RESULTS: The RT-PCR assays were found to be specific for their respective serotype and did not cross-react with other flaviviruses or human mRNA. All assays had a linear dynamic range of 10(2) to 10(6) copies/reaction with detection limits between 12 and 44 copies/reaction. When testing sera from 85 confirmed acute dengue cases, the serotype-specific DENV RT-PCR assays had 100 % positive agreement with the FDA-approved CDC DENV-1-4 RT-PCR assay performed in a singleplex format. Additionally 15 samples that tested negative in the CDC DENV-1-4- RT-PCR assay were found positive using the serotype-specific DENV RT-PCR assays. CONCLUSIONS: Our results suggest that these RT-PCR assays are useful alternatives to existing methods for serotyping DENV in clinical sera.


Subject(s)
Dengue Virus/classification , Dengue Virus/isolation & purification , Real-Time Polymerase Chain Reaction/methods , Cross Reactions , DNA Primers , Dengue/virology , Dengue Virus/genetics , Dengue Virus/immunology , Humans , Limit of Detection , Reverse Transcriptase Polymerase Chain Reaction/methods , Sensitivity and Specificity , Serotyping/methods , Serum/virology
17.
EFSA J ; 22(4): e8735, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38576537

ABSTRACT

Avian influenza viruses (AIV) remain prevalent among wild bird populations in the European Union and European Economic Area (EU/EEA), leading to significant illness in and death of birds. Transmission between bird and mammal species has been observed, particularly in fur animal farms, where outbreaks have been reported. While transmission from infected birds to humans is rare, there have been instances of exposure to these viruses since 2020 without any symptomatic infections reported in the EU/EEA. However, these viruses continue to evolve globally, and with the migration of wild birds, new strains carrying potential mutations for mammalian adaptation could be selected. If avian A(H5N1) influenza viruses acquire the ability to spread efficiently among humans, large-scale transmission could occur due to the lack of immune defences against H5 viruses in humans. The emergence of AIV capable of infecting mammals, including humans, can be facilitated by various drivers. Some intrinsic drivers are related to virus characteristics or host susceptibility. Other drivers are extrinsic and may increase exposure of mammals and humans to AIV thereby stimulating mutation and adaptation to mammals. Extrinsic drivers include the ecology of host species, such as including wildlife, human activities like farming practices and the use of natural resources, climatic and environmental factors. One Health measures to mitigate the risk of AIV adapting to mammals and humans focus on limiting exposure and preventing spread. Key options for actions include enhancing surveillance targeting humans and animals, ensuring access to rapid diagnostics, promoting collaboration between animal and human sectors, and implementing preventive measures such as vaccination. Effective communication to different involved target audiences should be emphasised, as well as strengthening veterinary infrastructure, enforcing biosecurity measures at farms, and reducing wildlife contact with domestic animals. Careful planning of poultry and fur animal farming, especially in areas with high waterfowl density, is highlighted for effective risk reduction.

18.
mBio ; : e0222423, 2023 Nov 10.
Article in English | MEDLINE | ID: mdl-37947415

ABSTRACT

Four molluscum contagiosum virus (MOCV) genotypes (MOCV1-4) and four subtype variants (MOCV1p, MOCV1va, MOCV1vb, and MOCV1vc) were partially characterized using restriction enzyme profiling in the early 1980s/1990s. However, complete genome sequences of only MOCV1 and MOCV2 are available. The evolutionary pathways of MOCV genotypes and subtype variants with unavailable sequences remain unclear, and also whether all MOCV genotypes/subtype variants can be reliably detected and appropriately categorized using available PCR-based protocols. We de novo fully characterized and functionally annotated 47 complete MOCV genomes, including two putative non-MOCV1/2 isolates, expanding the number of fully characterized MOCV genomes to 66. To ascertain the placement of any putative novel MOCV sequence into the restriction profiling typing scheme, we developed an original framework for extracting complete MOCV genome sequence-based restriction profiles and matching them with reference restriction profiles. We confirmed that two putative non-MOCV1/2 isolates represent the first complete genomes of MOCV3. Comprehensive phylogenomic, recombination, and restriction enzyme recognition site analysis of all 66 currently available MOCV genomes showed that they can be agglomerated into six phylogenetic subgroups (PG1-6), corresponding to the subtype variants from the pioneering studies. PG5 was a novel subtype variant of MOCV2, but no PGs corresponded to the subtype variants MOCV1vb or MOCV4. We showed that the phylogenetic subgroups may have diverged from the prototype MOCV genotype lineages following large-scale recombination events and hinted at partial sequence content of MOCV4 and direction of recombinant transfer in the events that spawned PG5 and the yet undetected subtype variant MOCV1vb.IMPORTANCEFour molluscum contagiosum virus (MOCV) genotypes (MOCV1-4) and four subtype variants were partially characterized using restriction enzyme profiling in the 1980s/1990s, but complete genome sequences of only MOCV1 and MOCV2 are available. The evolutionary pathways whereby genotypes/subtype variants with unavailable sequences emerged and whether all MOCVs can be detected using current diagnostic approaches remain unclear. We fully characterized 47 novel complete MOCV genomes, including the first complete MOCV3 genome, expanding the number of fully characterized genomes to 66. For reliably classifying the novel non-MOCV1/2 genomes, we developed and validated a framework for matching sequence-derived restriction maps with those defining MOCV subtypes in pioneering studies. Six phylogenetic subgroups (PG1-6) were identified, PG5 representing a novel MOCV2 subtype. The phylogenetic subgroups diverged from the prototype lineages following large-scale recombination events and hinted at partial sequence content of MOCV4 and direction of recombinant transfer in the events spawning PG5 and yet undetected MOCV1vb variant.

19.
Anal Bioanal Chem ; 403(2): 443-55, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22362275

ABSTRACT

In (1)H NMR metabolomic datasets, there are often over a thousand peaks per spectrum, many of which change position drastically between samples. Automatic alignment, annotation, and quantification of all the metabolites of interest in such datasets have not been feasible. In this work we propose a fully automated annotation and quantification procedure which requires annotation of metabolites only in a single spectrum. The reference database built from that single spectrum can be used for any number of (1)H NMR datasets with a similar matrix. The procedure is based on the generalized fuzzy Hough transform (GFHT) for alignment and on Principal-components analysis (PCA) for peak selection and quantification. We show that we can establish quantities of 21 metabolites in several (1)H NMR datasets and that the procedure is extendable to include any number of metabolites that can be identified in a single spectrum. The procedure speeds up the quantification of previously known metabolites and also returns a table containing the intensities and locations of all the peaks that were found and aligned but not assigned to a known metabolite. This enables both biopattern analysis of known metabolites and data mining for new potential biomarkers among the unknowns.


Subject(s)
Amino Acids/analysis , Anti-Bacterial Agents/urine , Arabidopsis/chemistry , Ethionine/urine , Magnetic Resonance Spectroscopy/methods , Metabolomics/methods , Tetracycline/urine , Amino Acids/metabolism , Animals , Anti-Bacterial Agents/metabolism , Arabidopsis/metabolism , Automation , Ethionine/metabolism , Principal Component Analysis , Rats , Tetracycline/metabolism
20.
PLoS Negl Trop Dis ; 15(12): e0010110, 2021 12.
Article in English | MEDLINE | ID: mdl-34968388

ABSTRACT

BACKGROUND: The kinetoplastid protozoan Leishmania tropica mainly causes cutaneous leishmaniasis in humans in the Middle East, and relapse or treatment failure after treatment are common in this area. L. tropica's digenic life cycle includes distinct stages in the vector sandfly and the mammalian host. Sexual reproduction and genetic exchange appear to occur more frequently than in other Leishmania species. Understanding these processes is complicated by chromosome instability during cell division that yields aneuploidy, recombination and heterozygosity. This combination of rare recombination and aneuploid permits may reveal signs of hypothetical parasexual mating, where diploid cells fuse to form a transient tetraploid that undergoes chromosomal recombination and gradual chromosomal loss. METHODOLOGY/PRINCIPAL FINDINGS: The genome-wide SNP diversity from 22 L. tropica isolates showed chromosome-specific runs of patchy heterozygosity and extensive chromosome copy number variation. All these isolates were collected during 2007-2017 in Sweden from patients infected in the Middle East and included isolates from a patient possessing two genetically distinct leishmaniasis infections three years apart with no evidence of re-infection. We found differing ancestries on the same chromosome (chr36) across multiple samples: matching the reference genome with few derived alleles, followed by blocks of heterozygous SNPs, and then by clusters of homozygous SNPs with specific recombination breakpoints at an inferred origin of replication. Other chromosomes had similar marked changes in heterozygosity at strand-switch regions separating polycistronic transcriptional units. CONCLUSION/SIGNIFICANCE: These large-scale intra- and inter-chromosomal changes in diversity driven by recombination and aneuploidy suggest multiple mechanisms of cell reproduction and diversification in L. tropica, including mitotic, meiotic and parasexual processes. It underpins the need for more genomic surveillance of Leishmania, to detect emerging hybrids that could spread more widely and to better understand the association between genetic variation and treatment outcome. Furthering our understanding of Leishmania genome evolution and ancestry will aid better diagnostics and treatment for cutaneous leishmaniasis caused by L.tropica in the Middle East.


Subject(s)
Genome, Protozoan , Leishmania tropica/genetics , Leishmaniasis, Cutaneous/parasitology , Afghanistan , Chromosomes/genetics , DNA Copy Number Variations , DNA, Protozoan/genetics , Genetic Variation , Humans , Iran , Leishmania tropica/classification , Leishmania tropica/isolation & purification , Phylogeny , Polymorphism, Single Nucleotide , Recombination, Genetic , Syria
SELECTION OF CITATIONS
SEARCH DETAIL