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Miren Iturriza-Gomara

Bio: Miren Iturriza-Gomara is an academic researcher from University of Liverpool. The author has contributed to research in topics: Rotavirus & Rotavirus vaccine. The author has an hindex of 52, co-authored 178 publications receiving 9971 citations. Previous affiliations of Miren Iturriza-Gomara include Health Protection Agency & Christian Medical College & Hospital.


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Journal ArticleDOI
TL;DR: With increasing numbers of complete RV genome sequences becoming available, a standardized RV strain nomenclature system is needed, and the RCWG proposes that individual RV strains are named as follows: RV group/species of origin/country of identification/common name/year of identification /G- and P-type.
Abstract: In April 2008, a nucleotide-sequence-based, complete genome classification system was developed for group A rotaviruses (RVs). This system assigns a specific genotype to each of the 11 genome segments of a particular RV strain according to established nucleotide percent cutoff values. Using this approach, the genome of individual RV strains are given the complete descriptor of Gx-P[x]-Ix-Rx-Cx-Mx-Ax-Nx-Tx-Ex-Hx. The Rotavirus Classification Working Group (RCWG) was formed by scientists in the field to maintain, evaluate and develop the RV genotype classification system, in particular to aid in the designation of new genotypes. Since its conception, the group has ratified 51 new genotypes: as of April 2011, new genotypes for VP7 (G20-G27), VP4 (P[28]-P[35]), VP6 (I12-I16), VP1 (R5-R9), VP2 (C6-C9), VP3 (M7-M8), NSP1 (A15-A16), NSP2 (N6-N9), NSP3 (T8-T12), NSP4 (E12-E14) and NSP5/6 (H7-H11) have been defined for RV strains recovered from humans, cows, pigs, horses, mice, South American camelids (guanaco), chickens, turkeys, pheasants, bats and a sugar glider. With increasing numbers of complete RV genome sequences becoming available, a standardized RV strain nomenclature system is needed, and the RCWG proposes that individual RV strains are named as follows: RV group/species of origin/country of identification/common name/year of identification/G- and P-type. In collaboration with the National Center for Biotechnology Information (NCBI), the RCWG is also working on developing a RV-specific resource for the deposition of nucleotide sequences. This resource will provide useful information regarding RV strains, including, but not limited to, the individual gene genotypes and epidemiological and clinical information. Together, the proposed nomenclature system and the NCBI RV resource will offer highly useful tools for investigators to search for, retrieve, and analyze the ever-growing volume of RV genomic data.

836 citations

Journal ArticleDOI
TL;DR: The novel classification system allows the identification of (i) distinct genotypes, which probably followed separate evolutionary paths; (ii) interspecies transmissions and a plethora of reassortment events; and (iii) certain gene constellations that revealed a common origin between human Wa-like rotavirus strains and porcine rotav virus strains.
Abstract: Group A rotavirus classification is currently based on the molecular properties of the two outer layer proteins, VP7 and VP4, and the middle layer protein, VP6. As reassortment of all the 11 rotavirus gene segments plays a key role in generating rotavirus diversity in nature, a classification system that is based on all the rotavirus gene segments is desirable for determining which genes influence rotavirus host range restriction, replication, and virulence, as well as for studying rotavirus epidemiology and evolution. Toward establishing such a classification system, gene sequences encoding VP1 to VP3, VP6, and NSP1 to NSP5 were determined for human and animal rotavirus strains belonging to different G and P genotypes in addition to those available in databases, and they were used to define phylogenetic relationships among all rotavirus genes. Based on these phylogenetic analyses, appropriate identity cutoff values were determined for each gene. For the VP4 gene, a nucleotide identity cutoff value of 80% completely correlated with the 27 established P genotypes. For the VP7 gene, a nucleotide identity cutoff value of 80% largely coincided with the established G genotypes but identified four additional distinct genotypes comprised of murine or avian rotavirus strains. Phylogenetic analyses of the VP1 to VP3, VP6, and NSP1 to NSP5 genes showed the existence of 4, 5, 6, 11, 14, 5, 7, 11, and 6 genotypes, respectively, based on nucleotide identity cutoff values of 83%, 84%, 81%, 85%, 79%, 85%, 85%, 85%, and 91%, respectively. In accordance with these data, a revised nomenclature of rotavirus strains is proposed. The novel classification system allows the identification of (i) distinct genotypes, which probably followed separate evolutionary paths; (ii) interspecies transmissions and a plethora of reassortment events; and (iii) certain gene constellations that revealed (a) a common origin between human Wa-like rotavirus strains and porcine rotavirus strains and (b) a common origin between human DS-1-like rotavirus strains and bovine rotaviruses. These close evolutionary links between human and animal rotaviruses emphasize the need for close simultaneous monitoring of rotaviruses in animals and humans.

778 citations

Journal ArticleDOI
TL;DR: A Rotavirus Classification Working Group (RCWG) including specialists in molecular virology, infectious diseases, epidemiology, and public health was formed, which can assist in the appropriate delineation of new genotypes, thus avoiding duplications and helping minimize errors.
Abstract: Recently, a classification system was proposed for rotaviruses in which all the 11 genomic RNA segments are used (Matthijnssens et al. in J Virol 82:3204–3219, 2008). Based on nucleotide identity cut-off percentages, different genotypes were defined for each genome segment. A nomenclature for the comparison of complete rotavirus genomes was considered in which the notations Gx-P[x]-Ix-Rx-Cx-Mx-Ax-Nx-Tx-Ex-Hx are used for the VP7-VP4-VP6-VP1-VP2-VP3-NSP1-NSP2-NSP3-NSP4-NSP5/6 encoding genes, respectively. This classification system is an extension of the previously applied genotype-based system which made use of the rotavirus gene segments encoding VP4, VP7, VP6, and NSP4. In order to assign rotavirus strains to one of the established genotypes or a new genotype, a standard procedure is proposed in this report. As more human and animal rotavirus genomes will be completely sequenced, new genotypes for each of the 11 gene segments may be identified. A Rotavirus Classification Working Group (RCWG) including specialists in molecular virology, infectious diseases, epidemiology, and public health was formed, which can assist in the appropriate delineation of new genotypes, thus avoiding duplications and helping minimize errors. Scientists discovering a potentially new rotavirus genotype for any of the 11 gene segments are invited to send the novel sequence to the RCWG, where the sequence will be analyzed, and a new nomenclature will be advised as appropriate. The RCWG will update the list of classified strains regularly and make this accessible on a website. Close collaboration with the Study Group Reoviridae of the International Committee on the Taxonomy of Viruses will be maintained.

636 citations

Journal ArticleDOI
Katherine A Twohig1, Tommy Nyberg2, Asad Zaidi1, Simon Thelwall1  +604 moreInstitutions (2)
TL;DR: In this paper, the authors compared the severity of the delta variant compared with the alpha variant by determining the relative risk of hospital attendance outcomes and found that outbreaks of the Delta variant in unvaccinated populations might lead to a greater burden on health-care services than the alpha variants.
Abstract: Background The SARS-CoV-2 delta (B.1.617.2) variant was first detected in England in March, 2021. It has since rapidly become the predominant lineage, owing to high transmissibility. It is suspected that the delta variant is associated with more severe disease than the previously dominant alpha (B.1.1.7) variant. We aimed to characterise the severity of the delta variant compared with the alpha variant by determining the relative risk of hospital attendance outcomes. Methods This cohort study was done among all patients with COVID-19 in England between March 29 and May 23, 2021, who were identified as being infected with either the alpha or delta SARS-CoV-2 variant through whole-genome sequencing. Individual-level data on these patients were linked to routine health-care datasets on vaccination, emergency care attendance, hospital admission, and mortality (data from Public Health England's Second Generation Surveillance System and COVID-19-associated deaths dataset; the National Immunisation Management System; and NHS Digital Secondary Uses Services and Emergency Care Data Set). The risk for hospital admission and emergency care attendance were compared between patients with sequencing-confirmed delta and alpha variants for the whole cohort and by vaccination status subgroups. Stratified Cox regression was used to adjust for age, sex, ethnicity, deprivation, recent international travel, area of residence, calendar week, and vaccination status. Findings Individual-level data on 43 338 COVID-19-positive patients (8682 with the delta variant, 34 656 with the alpha variant; median age 31 years [IQR 17-43]) were included in our analysis. 196 (2·3%) patients with the delta variant versus 764 (2·2%) patients with the alpha variant were admitted to hospital within 14 days after the specimen was taken (adjusted hazard ratio [HR] 2·26 [95% CI 1·32-3·89]). 498 (5·7%) patients with the delta variant versus 1448 (4·2%) patients with the alpha variant were admitted to hospital or attended emergency care within 14 days (adjusted HR 1·45 [1·08-1·95]). Most patients were unvaccinated (32 078 [74·0%] across both groups). The HRs for vaccinated patients with the delta variant versus the alpha variant (adjusted HR for hospital admission 1·94 [95% CI 0·47-8·05] and for hospital admission or emergency care attendance 1·58 [0·69-3·61]) were similar to the HRs for unvaccinated patients (2·32 [1·29-4·16] and 1·43 [1·04-1·97]; p=0·82 for both) but the precision for the vaccinated subgroup was low. Interpretation This large national study found a higher hospital admission or emergency care attendance risk for patients with COVID-19 infected with the delta variant compared with the alpha variant. Results suggest that outbreaks of the delta variant in unvaccinated populations might lead to a greater burden on health-care services than the alpha variant. Funding Medical Research Council; UK Research and Innovation; Department of Health and Social Care; and National Institute for Health Research.

450 citations

Journal ArticleDOI
TL;DR: Methods and oligonucleotide primers are described to overcome failures to type G9, G 10 and P[11] rotavirus strains, and cross-reactivity identified between G10 and G3 rotaviruses.

411 citations


Cited by
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TL;DR: Each year, 31 pathogens caused 9.4 million episodes of foodborne illness, resulting in 55,961 hospitalizations and 1,351 deaths in the United States.
Abstract: Estimates of foodborne illness can be used to direct food safety policy and interventions. We used data from active and passive surveillance and other sources to estimate that each year 31 major pathogens acquired in the United States caused 9.4 million episodes of foodborne illness (90% credible interval [CrI] 6.6–12.7 million), 55,961 hospitalizations (90% CrI 39,534–75,741), and 1,351 deaths (90% CrI 712–2,268). Most (58%) illnesses were caused by norovirus, followed by nontyphoidal Salmonella spp. (11%), Clostridium perfringens (10%), and Campylobacter spp. (9%). Leading causes of hospitalization were nontyphoidal Salmonella spp. (35%), norovirus (26%), Campylobacter spp. (15%), and Toxoplasma gondii (8%). Leading causes of death were nontyphoidal Salmonella spp. (28%), T. gondii (24%), Listeria monocytogenes (19%), and norovirus (11%). These estimates cannot be compared with prior (1999) estimates to assess trends because different methods were used. Additional data and more refined methods can improve future estimates.

6,490 citations

Journal ArticleDOI
TL;DR: The approach to utilizing available RNA-Seq and other data types in the authors' manual curation process for vertebrate, plant, and other species is summarized, and a new direction for prokaryotic genomes and protein name management is described.
Abstract: The RefSeq project at the National Center for Biotechnology Information (NCBI) maintains and curates a publicly available database of annotated genomic, transcript, and protein sequence records (http://www.ncbi.nlm.nih.gov/refseq/). The RefSeq project leverages the data submitted to the International Nucleotide Sequence Database Collaboration (INSDC) against a combination of computation, manual curation, and collaboration to produce a standard set of stable, non-redundant reference sequences. The RefSeq project augments these reference sequences with current knowledge including publications, functional features and informative nomenclature. The database currently represents sequences from more than 55,000 organisms (>4800 viruses, >40,000 prokaryotes and >10,000 eukaryotes; RefSeq release 71), ranging from a single record to complete genomes. This paper summarizes the current status of the viral, prokaryotic, and eukaryotic branches of the RefSeq project, reports on improvements to data access and details efforts to further expand the taxonomic representation of the collection. We also highlight diverse functional curation initiatives that support multiple uses of RefSeq data including taxonomic validation, genome annotation, comparative genomics, and clinical testing. We summarize our approach to utilizing available RNA-Seq and other data types in our manual curation process for vertebrate, plant, and other species, and describe a new direction for prokaryotic genomes and protein name management.

4,104 citations

Journal ArticleDOI
TL;DR: The concerted and coordinated response that contained SARS is a triumph for global public health and provides a new paradigm for the detection and control of future emerging infectious disease threats.
Abstract: The severe acute respiratory syndrome (SARS) is responsible for the first pandemic of the 21st century. Within months after its emergence in Guangdong Province in mainland China, it had affected more than 8000 patients and caused 774 deaths in 26 countries on five continents. It illustrated dramatically the potential of air travel and globalization for the dissemination of an emerging infectious disease and highlighted the need for a coordinated global response to contain such disease threats. We review the cause, epidemiology, and clinical features of the disease.

2,167 citations

Journal Article
TL;DR: High-dose of intravenous immunoglobulin (0.4 g/kg daily for 5 days) and PE are equally effective in intermediate and severe forms and the choice between the two treatments depends on their respective contra-indications and local availability.
Abstract: L'incidence annuelle du syndrome de Guillain-Barre est de 1,5/100000 habitants La mortalite actuelle est estimee a environ 5 % d'apres des essais therapeutiques recents, bien conduits Dix pour cent des malades gardent des sequelles motrices tres invalidantes un an apres le debut des premiers signes neurologiques La prise en charge de ces malades necessite des equipes entrainees, multidisciplinaires, pouvant pratiquer l'ensemble des therapeutiques specifiques La corticotherapie per os'ou par voie intraveineuse est inefficace Les echanges plasmatiques sont le premier traitement dont l'efficacite a ete demontree par rapport a un groupe controle Les indications sont maintenant mieux connues Les formes benignes (marche possible) beneficient de 2 echanges plasmatiques; 2 echanges supplementaires sont realises en cas d'aggravation Dans les formes intermediaires (marche impossible) et les formes severes (recours a la ventilation mecanique), 4 echanges plasmatiques sont conseilles Il n'est pas utile d'augmenter leur nombre dans les formes severes ou en cas d'absence d'amelioration De fortes doses d'immunoglobulines donnees par voie intraveineuse (lq IV) [0,4 g/kg/j pendant 5 jours] sont aussi efficaces que les echanges plasmatiques dans les formes intermediaires et severes Dans ces formes, le choix entre Ig IV et echanges plasmatiques depend des contre-indications respectives de ces traitements et de leur faisabilite Les travaux en cours ont comme objectif de mieux preciser les indications respectives des echanges plasmatiques et des lq IV dans des formes de gravite differente, leur morbidite comparee, la dose optimale des lq IV

1,842 citations

Journal ArticleDOI
TL;DR: The strength of the correlation between norovirus outbreaks and survey results suggests that the population survey is sensitive to norov virus activity and that Norovirus may account for much of what is considered to be unspecified.
Abstract: To the Editor: The updated estimates of foodborne illness in the United States reported by Scallan et al. probably overestimate the occurrence of illness caused by unspecified agents because they did not account for the apparent sensitivity of the population survey to the occurrence of norovirus (1,2). The number of illnesses attributed to unspecified agents was derived from the simultaneous processes of extrapolation and subtraction: extrapolation from the population survey to create a base of diarrheal illnesses and subtraction of known agents from this base. Scallan et al. averaged illness rates from 3 successive population surveys to come up with a rate of 0.6 episodes of acute gastroenteritis per person per year. However, the individual rates were 0.49 (2000–2001), 0.54 (2002–2003), and 0.73 (2006–2007). The 2006–2007 survey was conducted at the time of widespread norovirus activity. The estimated rate of population illness was strongly correlated with the number of confirmed and suspected norovirus outbreaks reported to the Centers for Disease Control and Prevention Foodborne Disease Outbreak Surveillance System during each of the survey periods (300, 371, and 491, respectively; R2 = 0.97, p<0.0001). No other known agents were correlated with the population survey rates, and the total numbers of outbreaks were inversely correlated with the population survey data. The strength of the correlation between norovirus outbreaks and survey results suggests that the population survey is sensitive to norovirus activity and that norovirus may account for much of what is considered to be unspecified. The fact that the highest observed population rate was ≈50% greater than the lowest rate suggests that annual variation in norovirus activity may account for a considerable proportion of what otherwise seems to be unspecified. More thorough and timely investigation and reporting of outbreaks could facilitate the development of models to evaluate the number of illnesses and update them annually.

1,474 citations