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1.
Methods Mol Biol ; 2829: 185-194, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38951334

RESUMEN

Insect cell expression has been successfully used for the production of viral antigens as part of commercial vaccine development. As expression host, insect cells offer advantage over bacterial system by presenting the ability of performing post-translational modifications (PTMs) such as glycosylation and phosphorylation thus preserving the native functionality of the proteins especially for viral antigens. Insect cells have limitation in exactly mimicking some proteins which require complex glycosylation pattern. The recent advancement in insect cell engineering strategies could overcome this limitation to some extent. Moreover, cost efficiency, timelines, safety, and process adoptability make insect cells a preferred platform for production of subunit antigens for human and animal vaccines. In this chapter, we describe the method for producing the SARS-CoV2 spike ectodomain subunit antigen for human vaccine development and the virus like particle (VLP), based on capsid protein of porcine circovirus virus 2 (PCV2d) antigen for animal vaccine development using two different insect cell lines, SF9 & Hi5, respectively. This methodology demonstrates the flexibility and broad applicability of insect cell as expression host.


Asunto(s)
Antígenos Virales , Baculoviridae , Glicoproteína de la Espiga del Coronavirus , Animales , Baculoviridae/genética , Antígenos Virales/genética , Antígenos Virales/inmunología , Células Sf9 , Humanos , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismo , Proteínas Recombinantes/genética , Línea Celular , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Vacunas de Partículas Similares a Virus/genética , Vacunas de Partículas Similares a Virus/inmunología , Vacunas de Partículas Similares a Virus/biosíntesis , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Glicosilación , Insectos/genética , Spodoptera , Vacunas contra la COVID-19/genética , Vacunas contra la COVID-19/inmunología
2.
Influenza Other Respir Viruses ; 18(7): e13348, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38949103

RESUMEN

Understanding the clinical spectrum of SARS-CoV-2 infection, including the asymptomatic fraction, is important as asymptomatic individuals are still able to infect other individuals and contribute to ongoing transmission. The WHO Unity Household transmission investigation (HHTI) protocol provides a platform for the prospective and systematic collection of high-quality clinical, epidemiological, serological and virological data from SARS-CoV-2 confirmed cases and their household contacts. These data can be used to understand key severity and transmissibility parameters-including the asymptomatic proportion-in relation to local epidemic context and help inform public health response. We aimed to estimate the asymptomatic proportion of SARS-CoV-2 Omicron variant infections in Unity-aligned HHTIs. We conducted a systematic review and meta-analysis in alignment with the PRISMA 2020 guidelines and registered our systematic review on PROSPERO (CRD42022378648). We searched EMBASE, Web of Science, MEDLINE and bioRxiv and medRxiv from 1 November 2021 to 22 August 2023. We identified 8368 records, of which 98 underwent full text review. We identified only three studies for data extraction, with substantial variation in study design and corresponding estimates of the asymptomatic proportion. As a result, we did not generate a pooled estimate or I2 metric. The limited number of quality studies that we identified highlights the need for improved preparedness and response capabilities to facilitate robust HHTI implementation, analysis and reporting, to better inform national, regional and global risk assessments and policymaking.


Asunto(s)
Infecciones Asintomáticas , COVID-19 , Composición Familiar , SARS-CoV-2 , Humanos , Infecciones Asintomáticas/epidemiología , COVID-19/epidemiología , COVID-19/transmisión , COVID-19/virología , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación
3.
Nat Commun ; 15(1): 5503, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38951531

RESUMEN

Proline is widely known as the only proteogenic amino acid with a secondary amine. In addition to its crucial role in protein structure, the secondary amino acid modulates neurotransmission and regulates the kinetics of signaling proteins. To understand the structural basis of proline import, we solved the structure of the proline transporter SIT1 in complex with the COVID-19 viral receptor ACE2 by cryo-electron microscopy. The structure of pipecolate-bound SIT1 reveals the specific sequence requirements for proline transport in the SLC6 family and how this protein excludes amino acids with extended side chains. By comparing apo and substrate-bound SIT1 states, we also identify the structural changes that link substrate release and opening of the cytoplasmic gate and provide an explanation for how a missense mutation in the transporter causes iminoglycinuria.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , Microscopía por Crioelectrón , Prolina , SARS-CoV-2 , Enzima Convertidora de Angiotensina 2/metabolismo , Enzima Convertidora de Angiotensina 2/química , Enzima Convertidora de Angiotensina 2/genética , Prolina/metabolismo , Humanos , SARS-CoV-2/metabolismo , SARS-CoV-2/genética , COVID-19/virología , COVID-19/metabolismo , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Sistemas de Transporte de Aminoácidos Neutros/genética , Sistemas de Transporte de Aminoácidos Neutros/química , Modelos Moleculares
4.
J Med Microbiol ; 73(7)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38963412

RESUMEN

Introduction. In India, the SARS-CoV-2 Delta wave (2020-2021) faded away with the advent of the Omicron variants (2021-present). Dengue incidences were observed to be less in Southeast Asia during the active years of the pandemic (2020-2021). However, dengue virus type 3 (DV3) cases were increasingly reported in this region (including India) concurrent with the progression of the Omicron waves since 2022.Hypothesis. What could be the reason(s) behind this unusual DV3 surge after an overall dip in dengue incidences in many parts of Southeast Asia?Aim. We, therefore, investigated the current state of cross-reactivity of prevalent (Omicron era) SARS-CoV-2 serums with different DV serotypes and evaluated the impact of such serums on DV neutralization in cell culture.Methodology. Fifty-five COVID-19 serum samples (January-September 2022) and three pre-pandemic archived serum samples from apparently healthy individuals were tested for DV or SARS-CoV-2 IgM/IgG using the lateral flow immunoassays. DV1-4 virus neutralization tests (VNTs) were done with the SARS-CoV-2 antibody (Ab)-positive serums in Huh7 cells. DV3 envelope (env) gene was PCR amplified and sequenced for three archived DV isolates, one from 2017 and two from 2021.Results. SARS-CoV-2 Ab-positive samples constituted 74.5 % of the serums. Of these, 41.5 % were DV cross-reactive and 58.5 % were not. The DV cross-reactive serums neutralized all DV serotypes (DV1-4), as per previous results and this study. The DV non-cross-reactive serums (58.5 %) also cross-neutralized DV1, 2 and 4 but increased DV3 infectivity by means of antibody-dependent enhancement of infection as evident from significantly higher DV3 titres in VNT compared to control serums. The DV3 envelope was identical among the three isolates, including isolate 1 used in VNTs. Our results suggest that DV cross-reactivity of SARS-CoV-2 serums diminished with the shift from Delta to Omicron prevalence. Such COVID-19 serums (DV non-cross-reactive) might have played a major role in causing DV3 surge during the Omicron waves.Conclusion. Patients suspected of dengue or COVID-19 should be subjected to virus/antigen tests and serological tests for both the diseases for definitive diagnosis, prognosis and disease management.


Asunto(s)
Anticuerpos Antivirales , COVID-19 , Reacciones Cruzadas , Virus del Dengue , SARS-CoV-2 , Humanos , SARS-CoV-2/inmunología , SARS-CoV-2/genética , COVID-19/virología , COVID-19/epidemiología , COVID-19/sangre , COVID-19/inmunología , Anticuerpos Antivirales/sangre , Virus del Dengue/genética , Virus del Dengue/inmunología , Virus del Dengue/clasificación , India/epidemiología , Dengue/virología , Dengue/sangre , Dengue/epidemiología , Dengue/inmunología , Pruebas de Neutralización , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre
5.
Nat Commun ; 15(1): 5577, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38956082

RESUMEN

Recent advances in single-cell immune profiling have enabled the simultaneous measurement of transcriptome and T cell receptor (TCR) sequences, offering great potential for studying immune responses at the cellular level. However, integrating these diverse modalities across datasets is challenging due to their unique data characteristics and technical variations. Here, to address this, we develop the multimodal generative model mvTCR to fuse modality-specific information across transcriptome and TCR into a shared representation. Our analysis demonstrates the added value of multimodal over unimodal approaches to capture antigen specificity. Notably, we use mvTCR to distinguish T cell subpopulations binding to SARS-CoV-2 antigens from bystander cells. Furthermore, when combined with reference mapping approaches, mvTCR can map newly generated datasets to extensive T cell references, facilitating knowledge transfer. In summary, we envision mvTCR to enable a scalable analysis of multimodal immune profiling data and advance our understanding of immune responses.


Asunto(s)
COVID-19 , Receptores de Antígenos de Linfocitos T , SARS-CoV-2 , Análisis de la Célula Individual , Transcriptoma , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/inmunología , Análisis de la Célula Individual/métodos , Humanos , SARS-CoV-2/inmunología , SARS-CoV-2/genética , COVID-19/inmunología , COVID-19/virología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Perfilación de la Expresión Génica/métodos , Antígenos Virales/inmunología , Antígenos Virales/genética
6.
Sci Rep ; 14(1): 15058, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38956433

RESUMEN

Since the COVID-19 pandemic, the diversity of clinical manifestations in patients has been a tremendous challenge. It seems that genetic variations, as one of the players, contribute to the variety of symptoms. Genome-wide association studies have demonstrated the influence of certain genomic regions on the disease prognosis. Particularly, a haplotype at 3p21.31 locus, inherited from Neanderthals, showed an association with COVID-19 severity. Despite several studies regarding this haplotype, some key variants are not sufficiently addressed. In the present study, we investigated the association of rs17713054 at 3p21.31 with COVID-19 severity. We analyzed the genotype of 251 Iranian COVID-19 patients (151 patients with asymptomatic to mild form as control and 100 patients with severe to critical symptoms without any comorbidities as case group) using the ARMS-PCR method. Results demonstrated that the A allele confers an almost twofold increased risk for COVID-19 severity (P value = 0.008). The AA genotype also raises the risk by more than 11 times following the recessive model (P value = 0.013). In conclusion, the A allele in rs17713054 was a risk allele in Iranian patients and was independently associated with COVID-19 severity. More studies are beneficial to confirm these findings in other populations and to develop strategies for risk assessment, prevention, and personalized medicine.


Asunto(s)
COVID-19 , Predisposición Genética a la Enfermedad , Hombre de Neandertal , Polimorfismo de Nucleótido Simple , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Humanos , COVID-19/genética , COVID-19/virología , COVID-19/epidemiología , Irán/epidemiología , Hombre de Neandertal/genética , Masculino , Femenino , Persona de Mediana Edad , Animales , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Adulto , Haplotipos , Cromosomas Humanos Par 3/genética , Alelos , Estudio de Asociación del Genoma Completo , Genotipo , Anciano
7.
Euro Surveill ; 29(27)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38967016

RESUMEN

BackgroundEffective pandemic preparedness requires robust severe acute respiratory infection (SARI) surveillance. However, identifying SARI patients based on symptoms is time-consuming. Using the number of reverse transcription (RT)-PCR tests or contact and droplet precaution labels as a proxy for SARI could accurately reflect the epidemiology of patients presenting with SARI.AimWe aimed to compare the number of RT-PCR tests, contact and droplet precaution labels and SARI-related International Classification of Disease (ICD)-10 codes and evaluate their use as surveillance indicators.MethodsPatients from all age groups hospitalised at Leiden University Medical Center between 1 January 2017 up to and including 30 April 2023 were eligible for inclusion. We used a clinical data collection tool to extract data from electronic medical records. For each surveillance indicator, we plotted the absolute count for each week, the incidence proportion per week and the correlation between the three surveillance indicators.ResultsWe included 117,404 hospital admissions. The three surveillance indicators generally followed a similar pattern before and during the COVID-19 pandemic. The correlation was highest between contact and droplet precaution labels and ICD-10 diagnostic codes (Pearson correlation coefficient: 0.84). There was a strong increase in the number of RT-PCR tests after the start of the COVID-19 pandemic.DiscussionAll three surveillance indicators have advantages and disadvantages. ICD-10 diagnostic codes are suitable but are subject to reporting delays. Contact and droplet precaution labels are a feasible option for automated SARI surveillance, since these reflect trends in SARI incidence and may be available real-time.


Asunto(s)
COVID-19 , Infecciones del Sistema Respiratorio , SARS-CoV-2 , Humanos , Países Bajos/epidemiología , COVID-19/epidemiología , SARS-CoV-2/genética , Masculino , Femenino , Adulto , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/diagnóstico , Persona de Mediana Edad , Anciano , Pandemias , Niño , Hospitalización/estadística & datos numéricos , Vigilancia de la Población/métodos , Adolescente , Preescolar , Incidencia , Clasificación Internacional de Enfermedades , Lactante , Prueba de Estudio Conceptual , Adulto Joven , Síndrome Respiratorio Agudo Grave/epidemiología , Síndrome Respiratorio Agudo Grave/diagnóstico , Anciano de 80 o más Años
8.
PLoS One ; 19(7): e0306554, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38968178

RESUMEN

The differences of SARS-CoV-2 variants brought the changes of transmission characteristics and clinical manifestations during the prevalence of COVID-19. In order to explore the evolution mechanisms of SARS-CoV-2 variants and the impacts of variant evolution, the classic SIR (Susceptible-Infected-Recovered) compartment model was modified to a generalized SVEIR (Susceptible-Vaccinated-Exposed-Infected-Recovered) compartment model with age-group and varying variants in this study. By using of the SVEIR model and least squares method, the optimal fittings against the surveillance data from Fujian Provincial Center for Disease Control and Prevention were performed for the five epidemics of Fujian Province. The main epidemiological characteristics such as basic reproduction number, effective reproduction number, sensitivity analysis, and cross-variant scenario investigations were extensively investigated during dynamic zero-COVID policy. The study results showed that the infectivities of the variants became fast from wild strain to the Delta variant, further to the Omicron variant. Meanwhile, the cross-variant investigations showed that the average incubation periods were shortened, and that the infection scales quickly enhanced. Further, the risk estimations with the new variants were performed without implements of the non-pharmaceutical interventions, based on the dominant variants XBB.1.9.1 and EG.5. The results of the risk estimations suggested that non-pharmaceutical interventions were necessary on the Chinese mainland for controlling severe infections and deaths, and also that the regular variant monitors were still workable against the aggressive variant evolution and the emergency of new transmission risks in the future.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/transmisión , COVID-19/epidemiología , COVID-19/virología , SARS-CoV-2/genética , SARS-CoV-2/patogenicidad , China/epidemiología , Número Básico de Reproducción , Modelos Epidemiológicos , Factores de Edad
9.
Nat Commun ; 15(1): 5606, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961055

RESUMEN

Viral mutations frequently outpace technologies used to detect harmful variants. Given the continual emergence of SARS-CoV-2 variants, platforms that can identify the presence of a virus and its propensity for infection are needed. Our electronic biomembrane sensing platform recreates distinct SARS-CoV-2 host cell entry pathways and reports the progression of entry as electrical signals. We focus on two necessary entry processes mediated by the viral Spike protein: virus binding and membrane fusion, which can be distinguished electrically. We find that closely related variants of concern exhibit distinct fusion signatures that correlate with trends in cell-based infectivity assays, allowing us to report quantitative differences in their fusion characteristics and hence their infectivity potentials. We use SARS-CoV-2 as our prototype, but we anticipate that this platform can extend to other enveloped viruses and cell lines to quantifiably assess virus entry.


Asunto(s)
COVID-19 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Internalización del Virus , SARS-CoV-2/genética , SARS-CoV-2/fisiología , Humanos , Glicoproteína de la Espiga del Coronavirus/metabolismo , Glicoproteína de la Espiga del Coronavirus/genética , COVID-19/virología , Fusión de Membrana , Sistema Libre de Células , Mutación , Acoplamiento Viral
10.
J Med Virol ; 96(7): e29752, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38949191

RESUMEN

Antiviral signaling, immune response and cell metabolism are dysregulated by SARS-CoV-2, the causative agent of COVID-19. Here, we show that SARS-CoV-2 accessory proteins ORF3a, ORF9b, ORF9c and ORF10 induce a significant mitochondrial and metabolic reprogramming in A549 lung epithelial cells. While ORF9b, ORF9c and ORF10 induced largely overlapping transcriptomes, ORF3a induced a distinct transcriptome, including the downregulation of numerous genes with critical roles in mitochondrial function and morphology. On the other hand, all four ORFs altered mitochondrial dynamics and function, but only ORF3a and ORF9c induced a marked alteration in mitochondrial cristae structure. Genome-Scale Metabolic Models identified both metabolic flux reprogramming features both shared across all accessory proteins and specific for each accessory protein. Notably, a downregulated amino acid metabolism was observed in ORF9b, ORF9c and ORF10, while an upregulated lipid metabolism was distinctly induced by ORF3a. These findings reveal metabolic dependencies and vulnerabilities prompted by SARS-CoV-2 accessory proteins that may be exploited to identify new targets for intervention.


Asunto(s)
COVID-19 , Mitocondrias , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Mitocondrias/metabolismo , COVID-19/metabolismo , COVID-19/virología , COVID-19/patología , Células A549 , Proteínas Reguladoras y Accesorias Virales/metabolismo , Proteínas Reguladoras y Accesorias Virales/genética , Transcriptoma , Sistemas de Lectura Abierta , Proteínas Virales/genética , Proteínas Virales/metabolismo , Proteínas Viroporinas
11.
Antimicrob Resist Infect Control ; 13(1): 73, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38971822

RESUMEN

The implementation of isolation precautions for patients with suspected Coronavirus Disease 2019 (COVID-19) and pending test results is resource intensive. Due to the limited availability of single-bed rooms at our institution, we isolated patients with suspected COVID-19 together with patients without suspected COVID-19 on-site in multiple-bed rooms until SARS-CoV-2-test results were available. We evaluated the likelihood of SARS-CoV-2 transmission to individuals sharing the room with patients isolated on-site. This observational study was performed at the University Hospital Basel, Switzerland, from 03/20 - 11/20. Secondary attack rates were compared between patients hospitalized in multiple-bed rooms and exposed to individuals subjected to on-site isolation precautions (on-site isolation group), and patients exposed to individuals initially not identified as having COVID-19, and not placed under isolation precautions until the diagnosis was suspected (control group). Transmission events were confirmed by whole-genome sequencing. Among 1,218 patients with suspected COVID-19, 67 (5.5%) tested positive for SARS-CoV-2. Of these, 21 were isolated on-site potentially exposing 27 patients sharing the same room. Median contact time was 12 h (interquartile range 7-18 h). SARS-CoV-2 transmission was identified in none of the patients in the on-site isolation group vs. 10/63 (15.9%) in the control group (p = 0.03). Isolation on-site of suspected COVID-19-patients in multiple-bed rooms avoided single-room occupancy and subsequent in-hospital relocation for many patients without confirmed SARS-CoV-2-infection. The absence of secondary transmission among the exposed patients in the on-site isolation group allows for assessment of the risk/benefit ratio of this strategy given the limitation of a small sample size.


Asunto(s)
COVID-19 , Aislamiento de Pacientes , Habitaciones de Pacientes , SARS-CoV-2 , Humanos , COVID-19/transmisión , COVID-19/epidemiología , COVID-19/diagnóstico , Femenino , Masculino , Suiza/epidemiología , Persona de Mediana Edad , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Anciano , Adulto , Anciano de 80 o más Años , Hospitales Universitarios
12.
Ann Ist Super Sanita ; 60(2): 85-88, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38984621

RESUMEN

The "Investigating and translating genomic evidence for public health response to SARS-CoV-2 (INSIDE SARS-CoV-2)" project is part of the initiative "Joint science and technology cooperation call for joint project proposals for the years 2021-2023" promoted by the Italian Ministry of Foreign Affairs and International Cooperation (MAECI) and the Republic of India. To start the project activities, the pandemic response and the epidemiological situation in Italy and in India, together with the genomic surveillance strategies for SARS-CoV-2 virus in the two countries, are here described.


Asunto(s)
COVID-19 , Genómica , Salud Pública , SARS-CoV-2 , COVID-19/epidemiología , Humanos , Italia/epidemiología , SARS-CoV-2/genética , India/epidemiología , Pandemias , Cooperación Internacional , Genoma Viral
13.
Front Cell Infect Microbiol ; 14: 1406091, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38988812

RESUMEN

The Coronavirus Disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has incurred devastating human and economic losses. Vaccination remains the most effective approach for controlling the COVID-19 pandemic. Nonetheless, the sustained evolution of SARS-CoV-2 variants has provoked concerns among the scientific community regarding the development of next-generation COVID-19 vaccines. Among these, given their safety, immunogenicity, and flexibility to display varied and native epitopes, virus-like particle (VLP)-based vaccines represent one of the most promising next-generation vaccines. In this review, we summarize the advantages and characteristics of VLP platforms, strategies for antigen display, and current clinical trial progress of SARS-CoV-2 vaccines based on VLP platforms. Importantly, the experience and lessons learned from the development of SARS-CoV-2 VLP vaccines provide insights into the development of strategies based on VLP vaccines to prevent future coronavirus pandemics and other epidemics.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Vacunas de Partículas Similares a Virus , Humanos , Vacunas contra la COVID-19/inmunología , Vacunas de Partículas Similares a Virus/inmunología , COVID-19/prevención & control , COVID-19/inmunología , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Animales , Ensayos Clínicos como Asunto
14.
J Infect Dev Ctries ; 18(6): 851-861, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38990988

RESUMEN

INTRODUCTION: In Senegal, molecular diagnosis was widely used for the detection and management of COVID-19 patients. However, genomic surveillance was very limited in the public sector. This study aimed to share the experience of a Senegalese public sector laboratory in response to the COVID-19 pandemic, and to describe the distribution of variants circulating in 2020 and 2021. METHODOLOGY: From July 2020 to December 2021, SARS-CoV-2 qRT-PCR was performed on nasopharyngeal samples from travelers and symptomatic patients at the Bacteriology and Virology Laboratory (LBV) of the Aristide le Dantec University Teaching Hospital. Samples with a cycle threshold (Ct) ≤ 30 were selected for whole-genome sequencing (WGS) using the Nanopore technology. In-house scripts were developed to study the spatial and temporal distribution of SARS-CoV-2 variants in Senegal, using our sequences and those retrieved from the GISAID database. RESULTS: Of 8,207 patients or travelers screened for SARS-CoV-2, 970 (11.8%) were positive and 386 had a Ct ≤ 30. WGS was performed on 133 samples. Concomitantly with high-quality sequences deposited in the GISAID database covering nine cities in Senegal in 2020 and 2021 (n = 1,539), we observed a high circulation of the 20A (B.1, B.1.416 and B.1.620) and 20B (B.1.1.420) lineages in 2020, while most of the samples belonged to Delta variants (AY34 and AY.34.1, 22%) in 2021. CONCLUSIONS: Despite its late involvement, COVID-19 diagnosis was routinely performed in LBV, but genomic characterization remained challenging. The genomic diversity of SARS-CoV-2 strains in Senegal reflected that observed worldwide during the first waves of the pandemic.


Asunto(s)
COVID-19 , Genoma Viral , SARS-CoV-2 , Humanos , Senegal/epidemiología , COVID-19/epidemiología , COVID-19/virología , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Secuenciación Completa del Genoma , Epidemiología Molecular , Nasofaringe/virología , Adulto , Masculino , Femenino , Filogenia , Persona de Mediana Edad
15.
Influenza Other Respir Viruses ; 18(7): e13316, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38992942

RESUMEN

INTRODUCTION: Amid coronavirus disease 2019 (COVID-19) pandemic, accurate detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for diagnosis management and breaking down transmission chains. We designed a national external quality assessment panel (EQAP) for SARS-CoV-2 molecular detection comprising working laboratories nationwide. METHODS: A molecular diagnostic EQA panel that consists of five samples for SARS CoV-2 testing was distributed to 141 public and private sector laboratories across country. These samples contain different concentrations of SARS-CoV-2 to evaluate the sensitivity of commercial kits available. RESULTS: Sensitivity among public and private sector laboratories was variable, particularly lower SARS-CoV-2 concentrations significantly increased the risk of false-negative tests, whereas Ct values of accurately tested SARS-CoV-2 specimens increased as concentration decreased. These findings highlighted that performance of used commercial kits was not significantly correlated to various extraction or PCR methods. CONCLUSION: This study highlights the need for a national external quality assessment panel (EQAP) in the country to improve the quality of the healthcare system while ensuring the accuracy and reliability of results. Furthermore, EQAPs can help laboratories meet accreditation and regulatory requirements. However, continued participation in EQAP is recommended for quality enhancement of laboratories.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiología , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/genética , Pakistán/epidemiología , Sensibilidad y Especificidad , Prueba de Ácido Nucleico para COVID-19/normas , Prueba de Ácido Nucleico para COVID-19/métodos , Técnicas de Diagnóstico Molecular/normas , Técnicas de Diagnóstico Molecular/métodos , Garantía de la Calidad de Atención de Salud , Prueba de COVID-19/métodos
16.
Rev Med Virol ; 34(4): e2569, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38986606

RESUMEN

We aimed to assess the performance of Ag-RDT and RT-qPCR with regard to detecting infectious SARS-CoV-2 in cell cultures, as their diagnostic test accuracy (DTA) compared to virus isolation remains largely unknown. We searched three databases up to 15 December 2021 for DTA studies. The bivariate model was used to synthesise the estimates. Risk of bias was assessed using QUADAS-2/C. Twenty studies (2605 respiratory samples) using cell culture and at least one molecular test were identified. All studies were at high or unclear risk of bias in at least one domain. Three comparative DTA studies reported results on Ag-RDT and RT-qPCR against cell culture. Two studies evaluated RT-qPCR against cell culture only. Fifteen studies evaluated Ag-RDT against cell culture as reference standard in RT-qPCR-positive samples. For Ag-RDT, summary sensitivity was 93% (95% CI 78; 98%) and specificity 87% (95% CI 70; 95%). For RT-qPCR, summary sensitivity (continuity-corrected) was 98% (95% CI 95; 99%) and specificity 45% (95% CI 28; 63%). In studies relying on RT-qPCR-positive subsamples (n = 15), the summary sensitivity of Ag-RDT was 93% (95% CI 92; 93%) and specificity 63% (95% CI 63; 63%). Ag-RDT show moderately high sensitivity, detecting most but not all samples demonstrated to be infectious based on virus isolation. Although RT-qPCR exhibits high sensitivity across studies, its low specificity to indicate infectivity raises the question of its general superiority in all clinical settings. Study findings should be interpreted with caution due to the risk of bias, heterogeneity and the imperfect reference standard for infectivity.


Asunto(s)
COVID-19 , SARS-CoV-2 , Sensibilidad y Especificidad , Humanos , SARS-CoV-2/aislamiento & purificación , SARS-CoV-2/genética , SARS-CoV-2/patogenicidad , COVID-19/diagnóstico , COVID-19/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/normas , Técnicas de Cultivo de Célula/métodos , Prueba de COVID-19/métodos , Prueba de Ácido Nucleico para COVID-19/métodos , Prueba de Diagnóstico Rápido
17.
J Med Virol ; 96(7): e29801, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38988204

RESUMEN

SARS-CoV-2 Omicron lineages continue to emerge and evolve into new sublineages, causing infection waves throughout 2022 and 2023, which has been attributed to immune escape. We examined neutralizing antibody responses to the recently emerged SARS-CoV-2 JN.1 variant in comparison to ancestral D614G and Omicron BA.1, BA.2, BA.5, and XBB.1.5 variants. We tested 79 human sera from cohorts with different combinations of vaccinations and infections, including 23 individuals who had been repeatedly exposed to Omicron. Individuals with a monovalent XBB.1.5 vaccine booster or XBB.1.5 breakthrough infection had robust antibody levels against all variants tested; however, JN.1 evaded antibodies in individuals after single Omicron BA.1, BA.2 or BA.5 breakthrough infections. Moreover, in the non-vaccinated cohort, serum antibodies demonstrated almost no cross-neutralization activities against D614G, XBB.1.5 and JN.1. after infections with earlier Omicron variants. These findings show that SARS-CoV-2-immunity is heterogeneous, depending on different combinations of vaccinations and infections, and emphasize the importance of considering different immune-backgrounds when evaluating novel variants.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Inmunización Secundaria , SARS-CoV-2 , Humanos , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , COVID-19/inmunología , COVID-19/prevención & control , COVID-19/virología , Anticuerpos Antivirales/sangre , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Femenino , Masculino , Adulto , Persona de Mediana Edad , Vacunación , Pruebas de Neutralización , Anciano
18.
J Med Virol ; 96(7): e29797, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38988215

RESUMEN

Temperature and humidity are studied in the context of seasonal infections in temperate and tropical zones, but the relationship between viral trends and climate variables in temperate subtropical zones remains underexplored. Our retrospective study analyzes respiratory pathogen incidence and its correlation with climate data in a subtropical zone. Retrospective observational study at Moinhos de Vento Hospital, South Brazil, aiming to assess seasonal trends in respiratory pathogens, correlating them with climate data. The study included patients of all ages from various healthcare settings, with data collected between April 2022 and July 2023. Biological samples were analyzed for 24 pathogens using polymerase chain reaction and hybridization techniques; demographic variables were also collected. The data was analyzed descriptively and graphically. Spearman tests and Poisson regression were used as correlation tests. Tests were clustered according to all pathogens, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza viruses, rhinovirus, and respiratory syncytial virus (RSV). Between April 2022 and July 2023, 3329 tests showed a 71.6% positivity rate. Rhinovirus and RSV predominated, exhibiting seasonal patterns. Temperature was inversely correlated with the viruses, notably rhinovirus, but SARS-CoV-2 was positively correlated. Air humidity was positively correlated with all pathogens, RSV, rhinovirus, and atmospheric pressure with all pathogens and rhinovirus. Our results showed statistically significant correlations, with modest effect sizes. Our study did not evaluate causation effects. Despite the correlation between climate and respiratory pathogens, our work suggests additional factors influencing transmission dynamics. Our findings underscore the complex interplay between climate and respiratory infections in subtropical climates.


Asunto(s)
COVID-19 , Humedad , Estaciones del Año , Temperatura , Humanos , Estudios Retrospectivos , COVID-19/epidemiología , COVID-19/transmisión , COVID-19/virología , Brasil/epidemiología , Femenino , Masculino , Adulto , Persona de Mediana Edad , Niño , Adolescente , Preescolar , Anciano , Adulto Joven , Lactante , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Clima , Infecciones del Sistema Respiratorio/virología , Infecciones del Sistema Respiratorio/epidemiología , Clima Tropical , Recién Nacido , Rhinovirus/genética , Rhinovirus/aislamiento & purificación , Incidencia , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/virología , Anciano de 80 o más Años
19.
J Med Microbiol ; 73(7)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38995847

RESUMEN

Introduction. At the end of 2019 and the year before, there was a significant spread of measles in the World Health Organization (WHO) European Region.Gap statement. Among the countries that reported, a measles outbreak was Bosnia and Herzegovina (BiH).Aim. To describe the measles outbreak in BiH (an entity of the Federation of BiH, FBiH) in 2019.Methodology. Confirmatory IgM serology, measles nucleic acid detection by real-time RT-PCR and virus genotyping were done in the WHO-accredited laboratory for measles and rubella at the Clinical Center of the University of Sarajevo, Unit for Clinical Microbiology. Genotype was determined in all measles-RNA-positive cases by sequence analysis of the 450 nt fragment coding the C-terminal of measles virus nucleoprotein (N).Results. From 1 January to 31 December 2019, 1332 measles cases were reported, with the peak observed in April 2019 (413/1332, 31.01 %). Sarajevo Canton had the highest incidence, number of cases and percentage (206.4; 868/1332; 65.17 %) of measles cases. Around four-fifths of infected persons were unvaccinated (1086/1332, 81.53 %), while 4.58 % of the patients (61/1332) were immunized with one dose of measles-containing vaccine. The highest proportion of cases was found in children 0-6 years of age (738/1332, 55.41 %). Measles IgM positivity was determined in 75.88 % (346/456), while virus RNA was detected in 82.46 % (47/57) of the swab samples. All measles virus sequences belonged to genotype B3. SNP (position 216: C=>T) was detected in 1 of the 40 sequences obtained during this outbreak.Conclusion. Due to suboptimal immunization coverage, BiH belongs to countries at a high risk for measles outbreaks. Post-COVID-19 (coronavirus disease 2019) pandemic, targeted and tailored strategies are required to ensure routine vaccination demand and acceptance and broad partner and stakeholder group participation.


Asunto(s)
COVID-19 , Brotes de Enfermedades , Genotipo , Virus del Sarampión , Sarampión , Humanos , Sarampión/epidemiología , Sarampión/virología , Sarampión/prevención & control , Virus del Sarampión/genética , Virus del Sarampión/aislamiento & purificación , Virus del Sarampión/clasificación , Virus del Sarampión/inmunología , Niño , Masculino , Adulto , Preescolar , Adolescente , Femenino , Adulto Joven , Lactante , COVID-19/epidemiología , COVID-19/prevención & control , Bosnia y Herzegovina/epidemiología , Persona de Mediana Edad , Inmunoglobulina M/sangre , ARN Viral/genética , SARS-CoV-2/genética , SARS-CoV-2/inmunología , SARS-CoV-2/aislamiento & purificación , Vacuna Antisarampión/administración & dosificación , Anticuerpos Antivirales/sangre
20.
Vopr Virusol ; 69(3): 255-265, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38996374

RESUMEN

INTRODUCTION: Bats are natural reservoirs of coronaviruses (Coronaviridae), which have caused three outbreaks of human disease SARS, MERS and COVID-19 or SARS-2 over the past decade. The purpose of the work is to study the diversity of coronaviruses among bats inhabiting the foothills and mountainous areas of the Republics of Dagestan, Altai and the Kemerovo region. MATERIALS AND METHODS: Samples of bat oral swabs and feces were tested for the presence of coronavirus RNA by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: It has been shown that the greater horseshoe bats (Rhinolophus ferrumequinum), inhabiting the Republic of Dagestan, are carriers of two different coronaviruses. One of the two coronaviruses is a member of the Sarbecovius subgenus of the Betacoronavirus genus, which includes the causative agents of SARS and COVID-19. The second coronavirus is assigned to the Decacovirus subgenus of the Alphacoronavirus genus and is most similar to viruses identified among Rhinolophus spp. from European and Middle Eastern countries. In the Altai Republic and Kemerovo region, coronaviruses belonging to the genus Alphacoronavirus, subgenus Pedacovirus, were found in the smooth-nosed bats: Ikonnikov`s bat (Myotis ikonnikovi) and the eastern bat (Myotis petax). The virus from the Altai Republic from M. ikonnikovi is close to viruses from Japan and Korea, as well as viruses from Myotis spp. from European countries. The virus from the Kemerovo region from M. petax groups with coronaviruses from Myotis spp. from Asian countries and is significantly different from coronaviruses previously discovered in the same natural host.


Asunto(s)
Quirópteros , Animales , Quirópteros/virología , Siberia/epidemiología , Filogenia , Reservorios de Enfermedades/virología , Coronavirus/genética , Coronavirus/aislamiento & purificación , Coronavirus/clasificación , Humanos , Heces/virología , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , COVID-19/virología , COVID-19/epidemiología , COVID-19/veterinaria , Infecciones por Coronavirus/virología , Infecciones por Coronavirus/veterinaria , Infecciones por Coronavirus/epidemiología
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