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1.
JMIR Public Health Surveill ; 10: e52047, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38569175

RESUMEN

BACKGROUND: Prepandemic sentinel surveillance focused on improved management of winter pressures, with influenza-like illness (ILI) being the key clinical indicator. The World Health Organization (WHO) global standards for influenza surveillance include monitoring acute respiratory infection (ARI) and ILI. The WHO's mosaic framework recommends that the surveillance strategies of countries include the virological monitoring of respiratory viruses with pandemic potential such as influenza. The Oxford-Royal College of General Practitioner Research and Surveillance Centre (RSC) in collaboration with the UK Health Security Agency (UKHSA) has provided sentinel surveillance since 1967, including virology since 1993. OBJECTIVE: We aim to describe the RSC's plans for sentinel surveillance in the 2023-2024 season and evaluate these plans against the WHO mosaic framework. METHODS: Our approach, which includes patient and public involvement, contributes to surveillance objectives across all 3 domains of the mosaic framework. We will generate an ARI phenotype to enable reporting of this indicator in addition to ILI. These data will support UKHSA's sentinel surveillance, including vaccine effectiveness and burden of disease studies. The panel of virology tests analyzed in UKHSA's reference laboratory will remain unchanged, with additional plans for point-of-care testing, pneumococcus testing, and asymptomatic screening. Our sampling framework for serological surveillance will provide greater representativeness and more samples from younger people. We will create a biomedical resource that enables linkage between clinical data held in the RSC and virology data, including sequencing data, held by the UKHSA. We describe the governance framework for the RSC. RESULTS: We are co-designing our communication about data sharing and sampling, contextualized by the mosaic framework, with national and general practice patient and public involvement groups. We present our ARI digital phenotype and the key data RSC network members are requested to include in computerized medical records. We will share data with the UKHSA to report vaccine effectiveness for COVID-19 and influenza, assess the disease burden of respiratory syncytial virus, and perform syndromic surveillance. Virological surveillance will include COVID-19, influenza, respiratory syncytial virus, and other common respiratory viruses. We plan to pilot point-of-care testing for group A streptococcus, urine tests for pneumococcus, and asymptomatic testing. We will integrate test requests and results with the laboratory-computerized medical record system. A biomedical resource will enable research linking clinical data to virology data. The legal basis for the RSC's pseudonymized data extract is The Health Service (Control of Patient Information) Regulations 2002, and all nonsurveillance uses require research ethics approval. CONCLUSIONS: The RSC extended its surveillance activities to meet more but not all of the mosaic framework's objectives. We have introduced an ARI indicator. We seek to expand our surveillance scope and could do more around transmissibility and the benefits and risks of nonvaccine therapies.


Asunto(s)
COVID-19 , Vacunas contra la Influenza , Gripe Humana , Infecciones del Sistema Respiratorio , Virosis , Humanos , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Vigilancia de Guardia , Infecciones del Sistema Respiratorio/epidemiología , Organización Mundial de la Salud , Atención Primaria de Salud
3.
Lancet Reg Health Eur ; 32: 100681, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37671127

RESUMEN

Background: Thrombosis associated with thrombocytopenia was a matter of concern post first and second doses of BNT162b2 and ChAdOx1 COVID-19 vaccines. Therefore, it is important to investigate the risk of thrombocytopenic, thromboembolic and haemorrhagic events following a second dose of BNT162b2 and ChAdOx1 COVID-19 vaccines. Methods: We conducted a large-scale self-controlled case series analysis, using routine primary care data linked to hospital data, among 12.3 million individuals (16 years old and above) in England. We used the nationally representative Oxford-Royal College of General Practitioners (RCGP) sentinel network database with baseline and risk periods between 8th December 2020 and 11th June 2022. We included individuals who received two vaccine (primary) doses of the BNT162b2 mRNA (Pfizer-BioNTech) and two vaccine doses of ChAdOx1 nCoV-19 (Oxford-AstraZeneca) vaccines in our analyses. We carried out a self-controlled case series (SCCS) analysis for each outcome using a conditional Poisson regression model with an offset for the length of risk period. We reported the incidence rate ratios (IRRs) and 95% confidence intervals (CI) of thrombocytopenic, thromboembolic (including arterial and venous events) and haemorrhagic events, in the period of 0-27 days after receiving a second dose of BNT162b2 or ChAdOx1 vaccines compared to the baseline period (14 or more days prior to first dose, 28 or more days after the second dose and the time between 28 or more days after the first and 14 or more days prior to the second dose). We adjusted for a range of potential confounders, including age, sex, comorbidities and deprivation. Findings: Between December 8, 2020 and February 11, 2022, 6,306,306 individuals were vaccinated with two doses of BNT162b2 and 6,046,785 individuals were vaccinated with two doses of ChAdOx1. Compared to the baseline, our analysis show no increased risk of venous thromboembolic events (VTE) for both BNT162b2 (IRR 0.71, 95% CI: 0.65-0.770) and ChAdOx1 (IRR 0.91, 95% CI: 0.84-0.98); and similarly there was no increased risk for cerebral venous sinus thrombosis (CVST) for both BNT162b2 (IRR 0.87, 95% CI: 0.41-1.85) and ChAdOx1 (IRR 1.73, 95% CI: 0.82-3.68). We additionally report no difference in IRR for pulmonary embolus, and deep vein thrombosis, thrombocytopenia, including idiopathic thrombocytopenic purpura (ITP), and haemorrhagic events post second dose for both BNT162b2. Interpretation: Reassuringly, we found no associations between increased risk of thrombocytopenic, thromboembolic and haemorrhagic events post vaccination with second dose for either of these vaccines. Funding: Data and Connectivity: COVID-19 Vaccines Pharmacovigilance study.

4.
PLoS One ; 17(3): e0265585, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35358234

RESUMEN

The extensive genetic variation in the lipooligosaccharide (LOS) core biosynthesis gene cluster has led to the development of a classification system; with 8 classes (I-VIII) for Campylobacter coli (C. coli) LOS region and with 23 classes (A-W) or four groups (1-4) for Campylobacter jejuni (C. jejuni) LOS region. PCR based LOS locus type identification for C. jejuni clinical isolates from a UK hospital as well as in silico LOS locus analysis for C. jejuni and C. coli genome sequences from GenBank was carried out to determine the frequencies of various LOS genotypes in C. jejuni and C. coli. Analysis of LOS gene content in 60 clinical C. jejuni isolates and 703 C. jejuni genome sequences revealed that class B (Group 1) was the most abundant LOS class in C. jejuni. The hierarchy of C. jejuni LOS group prevalence (group 1 > group 2 > group 3 > group 4) as well as the hierarchy of the frequency of C. jejuni LOS classes present within the group 1 (B > C > A > R > M > V), group 2 (H/P > O > E > W), group 3 (F > K > S) and group 4 (G > L) was identified. In silico analysis of LOS gene content in 564 C. coli genome sequences showed class III as the most abundant LOS locus type in C. coli. In silico analysis of LOS gene content also identified three novel LOS types of C. jejuni and previously unknown LOS biosynthesis genes in C. coli LOS locus types I, II, III, V and VIII. This study provides C. jejuni and C. coli LOS loci class frequencies in a smaller collection of C. jejuni clinical isolates as well as within the larger, worldwide database of C. jejuni and C. coli.


Asunto(s)
Campylobacter coli , Campylobacter jejuni , Lipopolisacáridos , Familia de Multigenes , Campylobacter coli/clasificación , Campylobacter coli/genética , Campylobacter jejuni/clasificación , Campylobacter jejuni/genética , Lipopolisacáridos/genética
5.
J Clin Epidemiol ; 144: 8-15, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34923026

RESUMEN

OBJECTIVE: Collaboration between groups can facilitate the development of high-quality guidelines. While collaboration is often desirable, misunderstandings can occur. One method to minimize misunderstandings is the pre-specification of terms of engagement in a memorandum of understanding (MOU). This study considered when an MOU may be most helpful, and which key elements should be included. STUDY DESIGN AND SETTING: An international panel of representatives from guideline groups was convened. A literature review to identify publications and other documents relevant to the establishment of MOUs between two or more guideline groups, supplemented by available source documents, was used to inform development of a draft MOU resource. This was iteratively refined until consensus was achieved. RESULTS: The level of detail in an MOU may vary based on institutional preferences and the particular collaboration. Elements within an MOU include those pertaining to: (1) scope and purpose; (2) leadership and team; (3) methods and commitment; (4) review and endorsement; and (5) publication and dissemination. CONCLUSION: Since groups may have different expectations regarding how a collaboration will unfold, an MOU may mitigate preventable misunderstandings. The result may be a higher likelihood of producing a guideline without disruption and delay.

6.
Front Microbiol ; 11: 677, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32508756

RESUMEN

Lipooligosaccharide (LOS) is an integral component of the Campylobacter cell membrane with a structure of core oligosaccharides forming inner and outer core regions and a lipid A moiety. The gene content of the LOS core biosynthesis cluster exhibits extensive sequence variation, which leads to the production of variable cell surface LOS structures in Campylobacter. Some LOS outer core molecules in Campylobacter jejuni are molecular mimics of host structures (such as neuronal gangliosides) and are thought to trigger neuronal disorders (particularly Guillain-Barré syndrome and Miller Fisher syndrome) in humans. The extensive genetic variation in the LOS biosynthesis gene cluster, a majority of which occurs in the LOS outer core biosynthesis gene content present between lgtF and waaV, has led to the development of a classification system with 23 classes (A-W) and four groups (1-4) for the C. jejuni LOS region. This review presents an updated and simplified classification system for LOS typing alongside an overview of the frequency of C. jejuni LOS biosynthesis genotypes and structures in various C. jejuni populations.

8.
Gut ; 67(11): 1920-1941, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30154172

RESUMEN

Interest in the therapeutic potential of faecal microbiota transplant (FMT) has been increasing globally in recent years, particularly as a result of randomised studies in which it has been used as an intervention. The main focus of these studies has been the treatment of recurrent or refractory Clostridium difficile infection (CDI), but there is also an emerging evidence base regarding potential applications in non-CDI settings. The key clinical stakeholders for the provision and governance of FMT services in the UK have tended to be in two major specialty areas: gastroenterology and microbiology/infectious diseases. While the National Institute for Health and Care Excellence (NICE) guidance (2014) for use of FMT for recurrent or refractory CDI has become accepted in the UK, clear evidence-based UK guidelines for FMT have been lacking. This resulted in discussions between the British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS), and a joint BSG/HIS FMT working group was established. This guideline document is the culmination of that joint dialogue.


Asunto(s)
Infecciones por Clostridium/terapia , Trasplante de Microbiota Fecal/métodos , Tracto Gastrointestinal/microbiología , Antibacterianos/uso terapéutico , Clostridioides difficile/efectos de los fármacos , Gastroenterología/organización & administración , Humanos , Recurrencia , Sociedades Médicas , Donantes de Tejidos , Reino Unido
9.
BMC Genomics ; 11: 389, 2010 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-20565959

RESUMEN

BACKGROUND: Clostridium difficile is a Gram-positive, anaerobic, spore-forming bacterium that is responsible for C. difficile associated disease in humans and is currently the most common cause of nosocomial diarrhoea in the western world. This current status has been linked to the emergence of a highly virulent PCR-ribotype 027 strain. The aim of this work was to identify regions of sequence divergence that may be used as genetic markers of hypervirulent PCR-ribotype 027 strains and markers of the sequenced strain, CD630 by array comparative hybridisation. RESULTS: In this study, we examined 94 clinical strains of the most common PCR-ribotypes isolated in mainland Europe and the UK by array comparative genomic hybridisation. Our array was comprehensive with 40,097 oligonucleotides covering the C. difficile 630 genome and revealed a core genome for all the strains of 32%. The array also covered genes unique to two PCR-ribotype 027 strains, relative to C. difficile 630 which were represented by 681 probes. All of these genes were also found in the commonly occuring PCR-ribotypes 001 and 106, and the emerging hypervirulent PCR-ribotype 078 strains, indicating that these are markers for all highly virulent strains. CONCLUSIONS: We have fulfilled the aims of this study by identifying markers for CD630 and markers associated with hypervirulence, albeit genes that are not just indicative of PCR-ribotype 027 strains. We have also extended this study and have defined a more stringent core gene set compared to those previously published due to the comprehensive array coverage. Further to this we have defined a list of genes absent from non-toxinogenic strains and defined the nature of the specific toxin deletion in the strain CD37.


Asunto(s)
Clostridioides difficile/genética , Clostridioides difficile/patogenicidad , Hibridación Genómica Comparativa , Análisis de Secuencia por Matrices de Oligonucleótidos , Toxinas Bacterianas/genética , Análisis por Conglomerados , Farmacorresistencia Bacteriana/genética , Flagelos/genética , Genes Bacterianos/genética , Genes Reguladores/genética , Variación Genética , Reacción en Cadena de la Polimerasa , Reproducibilidad de los Resultados , Especificidad de la Especie , Reino Unido , Factores de Virulencia/genética
10.
J Bacteriol ; 191(7): 2392-9, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19181814

RESUMEN

Deletion of the lipooligosaccharide biosynthesis region (Cj1132c to Cj1152c) from the genome of Campylobacter jejuni NCTC11168 shows that the core is not required for viability. The mutant was attenuated for growth and has increased sensitivity to antibiotics and detergents. Natural transformation and invasion of cultured host cells was abolished.


Asunto(s)
Proteínas Bacterianas/genética , Campylobacter jejuni/genética , Eliminación de Gen , Lipopolisacáridos/biosíntesis , Viabilidad Microbiana , Familia de Multigenes , Proteínas Bacterianas/metabolismo , Vías Biosintéticas , Campylobacter jejuni/química , Campylobacter jejuni/crecimiento & desarrollo , Campylobacter jejuni/metabolismo , Lipopolisacáridos/química , Mutación
11.
Appl Environ Microbiol ; 71(11): 7504-14, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16269792

RESUMEN

Bacterial comparative genomics has been revolutionized by microarrays, but the power of any microarray is dependent on the number and diversity of gene reporters it contains. Staphylococcus aureus is an important human pathogen causing a wide range of invasive and toxin-mediated diseases, and more than 20% of the genome of any isolate consists of variable genes. Seven whole-genome sequences of S. aureus are available, and we exploited this rare opportunity to design, build, and validate a comprehensive, nonredundant PCR product microarray carrying reporters that represent every predicted open reading frame (3,623 probes). Such a comprehensive microarray necessitated a novel design strategy. Validation with the seven sequenced strains showed correct identification of 93.9% of genes present or absent/divergent but was dependent on the method of analysis chosen. Microarray data were highly reproducible, reducing the need for many replicate slides. Interpretation of microarray data was enhanced by focusing on the major areas of variation--the presence or absence of mobile genetic elements (MGEs). We compiled "composite genomes" of every individual MGE and visualized their distribution. This allowed the sensitive discrimination of related isolates, including the first clear description of how isolates of the same clone of epidemic methicillin-resistant S. aureus differ substantially in their carriage of MGEs. These MGEs carry virulence and resistance genes, suggesting differences in pathogenic potential. The novel methods of design and interpretation of data generated from this microarray will enable further studies of S. aureus evolution, epidemiology, and pathogenesis.


Asunto(s)
Genómica , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Reacción en Cadena de la Polimerasa/métodos , Proyectos de Investigación , Staphylococcus aureus/clasificación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Genoma Bacteriano , Humanos , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Staphylococcus aureus/genética
12.
Microbiology (Reading) ; 151(Pt 9): 2907-2922, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16151203

RESUMEN

The release of the complete genome sequences of Neisseria meningitidis MC58 and Z2491 along with access to the sequences of N. meningitidis FAM18 and Neisseria gonorrhoeae FA1090 allowed the construction of a pan-Neisseria microarray, with every gene in all four genomes represented. The microarray was used to analyse a selection of strains including all N. meningitidis serogroups and commensal Neisseria species. For each strain, genes were defined as present, divergent or absent using gack analysis software. Comparison of the strains identified genes that were conserved within N. meningitidis serogroup B strains but absent from all commensal strains tested, consisting of mainly virulence-associated genes and transmissible elements. The microarray was able to distinguish between pilin genes, pilC orthologues and serogroup-specific capsule biosynthetic genes, and to identify dam and drg genotypes. Previously described N. meningitidis genes involved in iron response, adherence to epithelial cells, and pathogenicity were compared to the microarray analysis. The microarray data correlated with other genetic typing methods and were able to predict genotypes for uncharacterized strains and thus offer the potential for a rapid typing method. The subset of pathogen-specific genes identified represents potential drug or vaccine targets that would not eliminate commensal neisseriae and the associated naturally acquired immunity.


Asunto(s)
Antígenos Bacterianos/genética , Genoma Bacteriano , Neisseria/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Neisseria/clasificación , Neisseria/patogenicidad , Virulencia/genética
13.
Appl Environ Microbiol ; 71(4): 2086-94, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15812042

RESUMEN

Explorative approaches such as DNA microarray experiments are becoming increasingly important in microbial research. Despite these major technical advancements, approaches to study multifactor experiments are still lacking. We have addressed this problem by using rotation testing and a novel multivariate analysis of variance (MANOVA) approach (50-50 MANOVA) to investigate interacting experimental factors in a complex experimental design. Furthermore, a new rotation testing based method was introduced to calculate false-discovery rates for each response. This novel analytical concept was used to investigate global survival mechanisms in the environment of the major food-borne pathogen C. jejuni. We simulated nongrowth environmental conditions by investigating combinations of the factors temperature (5 and 25 degrees C) and oxygen tension (anaerobic, microaerobic, and aerobic). Data were generated with DNA microarrays for information about gene expression patterns and Fourier transform infrared (FT-IR) spectroscopy to study global macromolecular changes in the cell. Microarray analyses showed that most genes were either unchanged or down regulated compared to the reference (day 0) for the conditions tested and that the 25 degrees C anaerobic condition gave the most distinct expression pattern with the fewest genes expressed. The few up-regulated genes were generally stress related and/or related to the cell envelope. We found, using FT-IR spectroscopy, that the amount of polysaccharides and oligosaccharides increased under the nongrowth survival conditions. Potential mechanisms for survival could be to down regulate most functions to save energy and to produce polysaccharides and oligosaccharides for protection against harsh environments. Basic knowledge about the survival mechanisms is of fundamental importance in preventing transmission of this bacterium through the food chain.


Asunto(s)
Campylobacter jejuni/crecimiento & desarrollo , Oxígeno/farmacología , Temperatura , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Campylobacter jejuni/genética , Campylobacter jejuni/metabolismo , Medios de Cultivo , ADN Bacteriano/análisis , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Modelos Biológicos , Análisis Multivariante , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , ARN Ribosómico 16S/genética , ARN Ribosómico 23S/genética , Espectroscopía Infrarroja por Transformada de Fourier
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