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1.
Bioinformatics ; 40(10)2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39360992

RESUMEN

MOTIVATION: Target enrichment strategies generate genomic data from multiple pathogens in a single process, greatly improving sensitivity over metagenomic sequencing and enabling cost-effective, high-throughput surveillance and clinical applications. However, uptake by research and clinical laboratories is constrained by an absence of computational tools that are specifically designed for the analysis of multi-pathogen enrichment sequence data. Here we present an analysis pipeline, Castanet, for use with multi-pathogen enrichment sequencing data. Castanet is designed to work with short-read data produced by existing targeted enrichment strategies, but can be readily deployed on any BAM file generated by another methodology. Also included are an optional graphical interface and installer script. RESULTS: In addition to genome reconstruction, Castanet reports method-specific metrics that enable quantification of capture efficiency, estimation of pathogen load, differentiation of low-level positives from contamination, and assessment of sequencing quality. Castanet can be used as a traditional end-to-end pipeline for consensus generation, but its strength lies in the ability to process a flexible, pre-defined set of pathogens of interest directly from multi-pathogen enrichment experiments. In our tests, Castanet consensus sequences were accurate reconstructions of reference sequences, including in instances where multiple strains of the same pathogen were present. Castanet performs effectively on standard computers and can process the entire output of a 96-sample enrichment sequencing run (50M reads) using a single batch process command, in $<$2 h. AVAILABILITY AND IMPLEMENTATION: Source code freely available under GPL-3 license at https://github.com/MultipathogenGenomics/castanet, implemented in Python 3.10 and supported in Ubuntu Linux 22.04. The data underlying this article are available in Europe Nucleotide Archives, at https://www.ebi.ac.uk/ena/browser/view/PRJEB77004.


Asunto(s)
Programas Informáticos , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Análisis de Secuencia de ADN/métodos , Metagenómica/métodos
2.
Virol J ; 21(1): 253, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39385182

RESUMEN

Varicella-zoster virus (VZV) is the etiological agent of chickenpox and shingles, diseases characterised by epidermal virus replication in skin and mucosa and the formation of blisters. We have previously shown that VZV infection has a profound effect on keratinocyte differentiation, altering the normal pattern of epidermal gene expression. In particular, VZV infection reduces expression of suprabasal keratins 1 and 10 and desmosomal proteins, disrupting epidermal structure to promote expression of a blistering phenotype. Here, we extend these findings to show that VZV infection upregulates the expression of keratin 15 (KRT15), a marker expressed by basal epidermal keratinocytes and hair follicles stem cells. We demonstrate that KRT15 is essential for VZV replication in the skin, since downregulation of KRT15 inhibits VZV replication in keratinocytes, while KRT15 exogenous overexpression supports viral replication. Importantly, our data show that VZV upregulation of KRT15 depends on the expression of the VZV immediate early gene ORF62. ORF62 is the only regulatory gene that is mutated in the live attenuated VZV vaccine and contains four of the five fixed mutations present in the VZV Oka vaccine. Our data indicate that the mutated vaccine ORF62 is not capable of upregulating KRT15, suggesting that this may contribute to the vaccine attenuation in skin. Taken together our data present a novel association between VZV and KRT15, which may open a new therapeutic window for a topical targeting of VZV replication in the skin via modulation of KRT15.


Asunto(s)
Herpesvirus Humano 3 , Queratinocitos , Regulación hacia Arriba , Vacunas Atenuadas , Replicación Viral , Humanos , Vacuna contra la Varicela/genética , Vacuna contra la Varicela/inmunología , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/fisiología , Proteínas Inmediatas-Precoces/genética , Proteínas Inmediatas-Precoces/metabolismo , Queratinocitos/virología , Transactivadores , Vacunas Atenuadas/genética , Vacunas Atenuadas/inmunología , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/metabolismo
4.
Genome Med ; 16(1): 111, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39252069

RESUMEN

BACKGROUND: Metagenomics is a powerful approach for the detection of unknown and novel pathogens. Workflows based on Illumina short-read sequencing are becoming established in diagnostic laboratories. However, high sequencing depth requirements, long turnaround times, and limited sensitivity hinder broader adoption. We investigated whether we could overcome these limitations using protocols based on untargeted sequencing with Oxford Nanopore Technologies (ONT), which offers real-time data acquisition and analysis, or a targeted panel approach, which allows the selective sequencing of known pathogens and could improve sensitivity. METHODS: We evaluated detection of viruses with readily available untargeted metagenomic workflows using Illumina and ONT, and an Illumina-based enrichment approach using the Twist Bioscience Comprehensive Viral Research Panel (CVRP), which targets 3153 viruses. We tested samples consisting of a dilution series of a six-virus mock community in a human DNA/RNA background, designed to resemble clinical specimens with low microbial abundance and high host content. Protocols were designed to retain the host transcriptome, since this could help confirm the absence of infectious agents. We further compared the performance of commonly used taxonomic classifiers. RESULTS: Capture with the Twist CVRP increased sensitivity by at least 10-100-fold over untargeted sequencing, making it suitable for the detection of low viral loads (60 genome copies per ml (gc/ml)), but additional methods may be needed in a diagnostic setting to detect untargeted organisms. While untargeted ONT had good sensitivity at high viral loads (60,000 gc/ml), at lower viral loads (600-6000 gc/ml), longer and more costly sequencing runs would be required to achieve sensitivities comparable to the untargeted Illumina protocol. Untargeted ONT provided better specificity than untargeted Illumina sequencing. However, the application of robust thresholds standardized results between taxonomic classifiers. Host gene expression analysis is optimal with untargeted Illumina sequencing but possible with both the CVRP and ONT. CONCLUSIONS: Metagenomics has the potential to become standard-of-care in diagnostics and is a powerful tool for the discovery of emerging pathogens. Untargeted Illumina and ONT metagenomics and capture with the Twist CVRP have different advantages with respect to sensitivity, specificity, turnaround time and cost, and the optimal method will depend on the clinical context.


Asunto(s)
Metagenómica , Virus , Metagenómica/métodos , Humanos , Virus/genética , Virus/aislamiento & purificación , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Virosis/diagnóstico , Virosis/virología , Metagenoma , Sensibilidad y Especificidad
5.
Lancet Infect Dis ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39265595

RESUMEN

BACKGROUND: No randomised controlled trials have yet reported on the effectiveness of molnupiravir on longer term outcomes for COVID-19. The PANORAMIC trial found molnupiravir reduced time to recovery in acute COVID-19 over 28 days. We aimed to report the effect of molnupiravir treatment for COVID-19 on wellbeing, severe and persistent symptoms, new infections, health care and social service use, medication use, and time off work at 3 months and 6 months post-randomisation. METHODS: This study is a follow-up to the main analysis, which was based on the first 28 days of follow-up and has been previously reported. For this multicentre, primary care, open-label, multi-arm, prospective randomised controlled trial conducted in the UK, participants were eligible if aged at least 50 years, or at least 18 years with a comorbidity, and unwell 5 days or less with confirmed COVID-19 in the community. Participants were randomly assigned to the usual care group or molnupiravir group plus usual care (800 mg twice a day for 5 days), which was stratified by age (<50 years or ≥50 years) and vaccination status (at least one dose: yes or no). The primary outcome was hospitalisation or death (or both) at 28 days; all longer term outcomes were considered to be secondary outcomes and included self-reported ratings of wellness (on a scale of 0-10), experiencing any symptom (fever, cough, shortness of breath, fatigue, muscle ache, nausea and vomiting, diarrhoea, loss of smell or taste, headache, dizziness, abdominal pain, and generally feeling unwell) rated as severe (moderately bad or major problem) or persistent, any health and social care use, health-related quality of life (measured by the EQ-5D-5L), time off work or school, new infections, and hospitalisation. FINDINGS: Between Dec 8, 2021, and April 27, 2022, 25 783 participants were randomly assigned to the molnupiravir plus usual care group (n=12 821) or usual care group (n=12 962). Long-term follow-up data were available for 23 008 (89·2%) of 25 784 participants with 11 778 (91·9%) of 12 821 participants in the molnupiravir plus usual care group and 11 230 (86·6%) of 12 963 in the usual care group. 22 806 (99·1%) of 23 008 had at least one previous dose of a SARS-CoV-2 vaccine. Any severe (3 months: adjusted risk difference -1·6% [-2·6% to -0·6%]; probability superiority [p(sup)]>0·99; number needed to treat [NNT] 62·5; 6 months: -1·9% [-2·9% to -0·9%]; p(sup)>0·99, NNT 52·6) or persistent symptoms (3 months: adjusted risk difference -2·1% [-2·9% to -1·5%]; p(sup)>0·99; NNT 47·6; 6 months: -2·5% [-3·3% to -1·6%]; p(sup)>0·99; NNT 40) were reduced in severity, and health-related quality of life (measured by the EQ-5D-5L) improved in the molnupiravir plus usual care group at 3 months and 6 months (3 months: adjusted mean difference 1·08 [0·65 to 1·53]; p(sup)>0·99; 6 months: 1·09 [0·63 to 1·55]; p(sup)>0·99). Ratings of wellness (3 months: adjusted mean difference 0·15 (0·11 to 0·19); p(sup)>0·99; 6 months: 0·12 (0·07 to 0·16); p(sup)>0·99), experiencing any more severe symptom (3 months; adjusted risk difference -1·6% [-2·6% to -0·6%]; p(sup)=0·99; 6 months: -1·9% [-2·9% to -0·9%]; p(sup)>0·99), and health-care use (3 months: adjusted risk difference -1·4% [-2·3% to -0·4%]; p(sup)>0·99; NNT 71·4; 6 months: -0·5% [-1·5% to 0·4%]; p(sup)>0·99; NNT 200) had high probabilities of superiority with molnupiravir treatment. There were significant differences in persistence of any symptom (910 [8·9%] of 10 190 vs 1027 [11%] of 9332, NNT 67) at 6 months, and reported time off work at 3 months (2017 [17·9%] of 11 274 vs 2385 [22·4%] of 10 628) and 6 months (460 [4·4%] of 10 562 vs 527 [5·4%] of 9846; NNT 100). There were no differences in hospitalisations at long-term follow-up. INTERPRETATION: In a vaccinated population, people treated with molnupiravir for acute COVID-19 felt better, experienced fewer and less severe COVID-19 associated symptoms, accessed health care less often, and took less time off work at 6 months. However, the absolute differences in this open-label design are small with high numbers needed to treat. FUNDING: UK Research and Innovation and National Institute for Health and Care Research.

6.
medRxiv ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39314969

RESUMEN

Aims/hypothesis: The nPOD-Virus group collaboratively applied innovative technologies to detect and sequence viral RNA in pancreas and other tissues from organ donors with type 1 diabetes. These analyses involved the largest number of pancreas samples collected to date. Methods: We analysed pancreas, spleen, pancreatic lymph nodes, and duodenum samples from the following donor groups: a) donors with type 1 diabetes (n=71), with (n=35) or without (n=36) insulin-containing islets, (b) donors with single or double islet autoantibody positivity without diabetes (n=22) and c) autoantibody-negative donors without diabetes (control donors) (n=74). Five research laboratories participated in this collaborative effort using approaches for unbiased discovery of RNA viruses (two RNA-Seq platforms), targeted detection of Enterovirus A-D species using RT-PCR, and tests for virus growth in cell-culture. Results: Direct RNA-Seq did not detect virus signal in pancreas samples, whereas RT-PCR detected enterovirus RNA confirmed by sequencing in low amounts in pancreas samples in three of the five donor groups, namely donors with type 1 diabetes with insulin-containing islets, 16% (5/32) donors being positive, donors with single islet autoantibody positivity with 53% (8/15) donors being positive, and non-diabetic donors with 8% (4/49) being enterovirus RNA positive. Detection of enterovirus RNA was significantly more frequent in single islet autoantibody-positive donors compared to donors with type 1 diabetes with insulin-deficient islets (p-value <0.001) and control donors (p-value 0.004). In some donors, pancreatic lymph nodes were also positive. RT-PCR detected enterovirus RNA also in spleen of a small number of donors and virus enrichment in susceptible cell lines before RT-PCR resulted in much higher rate in spleen positivity, particularly in donors with type 1 diabetes. Interestingly, the enterovirus strains detected did not cause a typical lytic infection, possibly reflecting their persistence-prone nature. Conclusions/interpretation: This was the largest coordinated effort to examine the presence of enterovirus RNA in pancreas of organ donors with type 1 diabetes, using a multitude of assays. These findings are consistent with the notion that both the subjects with type 1 diabetes and those with islet autoantibodies may carry a low-grade enterovirus infection in the pancreas and lymphoid tissues.

7.
Euro Surveill ; 29(39)2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39328162

RESUMEN

We report an increase in GII.17 norovirus outbreaks and sporadic infections of acute gastroenteritis in Austria, Germany, France, Ireland, the Netherlands, England and the United States during the 2023/24 season. A decrease in GII.4 coincided with GII.17 prevalence increasing to between 17% and 64% of all GII detections. Overall, 84% of the GII.17 strains clustered closely with strains first reported in Romania in 2021 and two new sub-lineages were identified. Norovirus surveillance and molecular characterisation should be prioritised this winter.


Asunto(s)
Infecciones por Caliciviridae , Brotes de Enfermedades , Gastroenteritis , Norovirus , Norovirus/genética , Norovirus/aislamiento & purificación , Infecciones por Caliciviridae/epidemiología , Infecciones por Caliciviridae/virología , Humanos , Gastroenteritis/epidemiología , Gastroenteritis/virología , Estados Unidos/epidemiología , Europa (Continente)/epidemiología , Genotipo , Filogenia , Prevalencia , ARN Viral/genética , Estaciones del Año , Heces/virología , Vigilancia de la Población
8.
EJHaem ; 5(4): 784-788, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39157618

RESUMEN

Congenital enterovirus infection can be associated with a pro-inflammatory state triggering haemophagocytic lymphohistiocytosis (HLH). Enteroviruses are also known to cause transient neutropenia in healthy children. Two infants presented with temperature instability, lethargy, thrombocytopaenia, hepatosplenomegaly and evidence of hyperinflammation in the setting of perinatal maternal rash and household contacts with gastrointestinal symptoms. Whilst HLH was successfully treated in both, protracted neutropenia persisted. Immune dysregulation with enterovirus in the neonatal period can provoke the generation of autoantibodies to hematologic cells giving rise to conditions such as autoimmune neutropenia. Sustained neutropaenia, after resolution of secondary infectious forms of HLH, requires investigation for underlying aetiologies.

10.
Lancet Microbe ; 5(7): 655-668, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38703782

RESUMEN

BACKGROUND: A SARS-CoV-2 controlled human infection model (CHIM) has been successfully established in seronegative individuals using a dose of 1×101 50% tissue culture infectious dose (TCID50) pre-alpha SARS-CoV-2 virus. Given the increasing prevalence of seropositivity to SARS-CoV-2, a CHIM that could be used for vaccine development will need to induce infection in those with pre-existing immunity. Our aim was to find a dose of pre-alpha SARS-CoV-2 virus that induced infection in previously infected individuals. METHODS: Healthy, UK volunteers aged 18-30 years, with proven (quantitative RT-PCR or lateral flow antigen test) previous SARS-CoV-2 infection (with or without vaccination) were inoculated intranasally in a stepwise dose escalation CHIM with either 1×101, 1×102, 1×10³, 1×104, or 1×105 TCID50 SARS-CoV-2/human/GBR/484861/2020, the same virus used in the seronegative CHIM. Post-inoculation, volunteers were quarantined in functionally negative pressure rooms (Oxford, UK) for 14 days and until 12-hourly combined oropharyngeal-nasal swabs were negative for viable virus by focus-forming assay. Outpatient follow-up continued for 12 months post-enrolment, with additional visits for those who developed community-acquired SARS-CoV-2 infection. The primary objective was to identify a safe, well tolerated dose that induced infection (defined as two consecutive SARS-CoV-2 positive PCRs starting 24 h after inoculation) in 50% of seropositive volunteers. This study is registered with ClinicalTrials.gov (NCT04864548); enrolment and follow-up to 12 months post-enrolment are complete. FINDINGS: Recruitment commenced on May 6, 2021, with the last volunteer enrolled into the dose escalation cohort on Nov 24, 2022. 36 volunteers were enrolled, with four to eight volunteers inoculated in each dosing group from 1×101 to 1×105 TCID50 SARS-CoV-2. All volunteers have completed quarantine, with follow-up to 12 months complete. Despite dose escalation to 1×105 TCID50, we were unable to induce sustained infection in any volunteers. Five (14%) of 36 volunteers were considered to have transient infection, based on the kinetic of their PCR-positive swabs. Transiently infected volunteers had significantly lower baseline mucosal and systemic SARS-CoV-2-specific antibody titres and significantly lower peripheral IFNγ responses against a CD8+ T-cell SARS-CoV-2 peptide pool than uninfected volunteers. 14 (39%) of 36 volunteers subsequently developed breakthrough infection with the omicron variant after discharge from quarantine. Most adverse events reported by volunteers in quarantine were mild, with fatigue (16 [44%]) and stuffy nose (16 [44%]) being the most common. There were no serious adverse events. INTERPRETATION: Our study demonstrates potent protective immunity induced by homologous vaccination and homologous or heterologous previous SARS-CoV-2 infection. The community breakthrough infections seen with the omicron variant supports the use of newer variants to establish a model with sufficient rate of infection for use in vaccine and therapeutic development. FUNDING: Wellcome Trust and Department for Health and Social Care.


Asunto(s)
Anticuerpos Antivirales , COVID-19 , SARS-CoV-2 , Humanos , Adulto , SARS-CoV-2/inmunología , COVID-19/prevención & control , COVID-19/inmunología , Masculino , Adulto Joven , Reino Unido/epidemiología , Femenino , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Adolescente , Voluntarios Sanos , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Vacunas contra la COVID-19/efectos adversos , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Vacunación/métodos
11.
Nat Microbiol ; 9(5): 1293-1311, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38622380

RESUMEN

Children infected with SARS-CoV-2 rarely progress to respiratory failure. However, the risk of mortality in infected people over 85 years of age remains high. Here we investigate differences in the cellular landscape and function of paediatric (<12 years), adult (30-50 years) and older adult (>70 years) ex vivo cultured nasal epithelial cells in response to infection with SARS-CoV-2. We show that cell tropism of SARS-CoV-2, and expression of ACE2 and TMPRSS2 in nasal epithelial cell subtypes, differ between age groups. While ciliated cells are viral replication centres across all age groups, a distinct goblet inflammatory subtype emerges in infected paediatric cultures and shows high expression of interferon-stimulated genes and incomplete viral replication. In contrast, older adult cultures infected with SARS-CoV-2 show a proportional increase in basaloid-like cells, which facilitate viral spread and are associated with altered epithelial repair pathways. We confirm age-specific induction of these cell types by integrating data from in vivo COVID-19 studies and validate that our in vitro model recapitulates early epithelial responses to SARS-CoV-2 infection.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , COVID-19 , Células Epiteliales , Mucosa Nasal , SARS-CoV-2 , Serina Endopeptidasas , Humanos , COVID-19/virología , SARS-CoV-2/fisiología , SARS-CoV-2/patogenicidad , SARS-CoV-2/genética , Enzima Convertidora de Angiotensina 2/metabolismo , Enzima Convertidora de Angiotensina 2/genética , Adulto , Persona de Mediana Edad , Anciano , Células Epiteliales/virología , Serina Endopeptidasas/metabolismo , Serina Endopeptidasas/genética , Mucosa Nasal/virología , Niño , Factores de Edad , Replicación Viral , Preescolar , Tropismo Viral , Masculino , Femenino , Anciano de 80 o más Años , Células Cultivadas , Adolescente , Lactante
12.
Virus Evol ; 10(1): veae001, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38486802

RESUMEN

Mutagenic antiviral drugs have shown promise against multiple viruses, but concerns have been raised about whether their use might promote the emergence of new and harmful viral variants. Recently, genetic signatures associated with molnupiravir use have been identified in the global SARS-COV-2 population. Here, we examine the consequences of using favipiravir and molnupiravir to treat SARS-CoV-2 infection in a hamster model, comparing viral genome sequence data collected from (1) untreated hamsters, and (2) from hamsters receiving effective and suboptimal doses of treatment. We identify a broadly linear relationship between drug dose and the extent of variation in treated viral populations, with a high proportion of this variation being composed of variants at frequencies of less than 1 per cent, below typical thresholds for variant calling. Treatment with an effective dose of antiviral drug was associated with a gain of between 7 and 10 variants per viral genome relative to drug-free controls: even after a short period of treatment a population founded by a transmitted virus could contain multiple sequence differences to that of the original host. Treatment with a suboptimal dose of drug showed intermediate gains of variants. No dose-dependent signal was identified in the numbers of single-nucleotide variants reaching frequencies in excess of 5 per cent. We did not find evidence to support the emergence of drug resistance or of novel immune phenotypes. Our study suggests that where onward transmission occurs, a short period of treatment with mutagenic drugs may be sufficient to generate a significant increase in the number of viral variants transmitted.

14.
Microb Genom ; 10(3)2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38445851

RESUMEN

Trachoma, a neglected tropical disease caused by Chlamydia trachomatis (Ct) serovars A-C, is the leading infectious cause of blindness worldwide. Africa bears the highest burden, accounting for over 86 % of global trachoma cases. We investigated Ct serovar A (SvA) and B (SvB) whole genome sequences prior to the induction of mass antibiotic drug administration in The Gambia. Here, we explore the factors contributing to Ct strain diversification and the implications for Ct evolution within the context of ocular infection. A cohort study in 2002-2003 collected ocular swabs across nine Gambian villages during a 6 month follow-up study. To explore the genetic diversity of Ct within and between individuals, we conducted whole-genome sequencing (WGS) on a limited number (n=43) of Ct-positive samples with an omcB load ≥10 from four villages. WGS was performed using target enrichment with SureSelect and Illumina paired-end sequencing. Out of 43 WGS samples, 41 provided sufficient quality for further analysis. ompA analysis revealed that 11 samples had highest identity to ompA from strain A/HAR13 (NC_007429) and 30 had highest identity to ompA from strain B/Jali20 (NC_012686). While SvB genome sequences formed two distinct village-driven subclades, the heterogeneity of SvA sequences led to the formation of many individual branches within the Gambian SvA subclade. Comparing the Gambian SvA and SvB sequences with their reference strains, Ct A/HAR13 and Ct B/Jali20, indicated an single nucleotide polymorphism accumulation rate of 2.4×10-5 per site per year for the Gambian SvA and 1.3×10-5 per site per year for SvB variants (P<0.0001). Variant calling resulted in a total of 1371 single nucleotide variants (SNVs) with a frequency >25 % in SvA sequences, and 438 SNVs in SvB sequences. Of note, in SvA variants, highest evolutionary pressure was recorded on genes responsible for host cell modulation and intracellular survival mechanisms, whereas in SvB variants this pressure was mainly on genes essential for DNA replication/repair mechanisms and protein synthesis. A comparison of the sequences between observed separate infection events (4-20 weeks between infections) suggested that the majority of the variations accumulated in genes responsible for host-pathogen interaction such as CTA_0166 (phospholipase D-like protein), CTA_0498 (TarP) and CTA_0948 (deubiquitinase). This comparison of Ct SvA and SvB variants within a trachoma endemic population focused on their local evolutionary adaptation. We found a different variation accumulation pattern in the Gambian SvA chromosomal genes compared with SvB, hinting at the potential of Ct serovar-specific variation in diversification and evolutionary fitness. These findings may have implications for optimizing trachoma control and prevention strategies.


Asunto(s)
Tracoma , Humanos , Tracoma/epidemiología , Tracoma/genética , Chlamydia trachomatis/genética , Gambia/epidemiología , Estudios de Cohortes , Estudios de Seguimiento , Genómica
15.
Nat Commun ; 15(1): 1652, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38396069

RESUMEN

Viral clearance, antibody response and the mutagenic effect of molnupiravir has not been elucidated in at-risk populations. Non-hospitalised participants within 5 days of SARS-CoV-2 symptoms randomised to receive molnupiravir (n = 253) or Usual Care (n = 324) were recruited to study viral and antibody dynamics and the effect of molnupiravir on viral whole genome sequence from 1437 viral genomes. Molnupiravir accelerates viral load decline, but virus is detectable by Day 5 in most cases. At Day 14 (9 days post-treatment), molnupiravir is associated with significantly higher viral persistence and significantly lower anti-SARS-CoV-2 spike antibody titres compared to Usual Care. Serial sequencing reveals increased mutagenesis with molnupiravir treatment. Persistence of detectable viral RNA at Day 14 in the molnupiravir group is associated with higher transition mutations following treatment cessation. Viral viability at Day 14 is similar in both groups with post-molnupiravir treated samples cultured up to 9 days post cessation of treatment. The current 5-day molnupiravir course is too short. Longer courses should be tested to reduce the risk of potentially transmissible molnupiravir-mutated variants being generated. Trial registration: ISRCTN30448031.


Asunto(s)
COVID-19 , Citidina/análogos & derivados , Hidroxilaminas , SARS-CoV-2 , Adulto , Humanos , SARS-CoV-2/genética , Pacientes Ambulatorios , Formación de Anticuerpos , Anticuerpos Antivirales , Antivirales/uso terapéutico
16.
Vox Sang ; 119(5): 447-459, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38419267

RESUMEN

BACKGROUND AND OBJECTIVES: Exclusion of blood donors with hepatitis B virus (HBV) core antibodies (anti-HBc) prevents transfusion-transmitted HBV infection but can lead to significant donor loss. As isolated anti-HBc positivity does not always indicate true past HBV infection, we have investigated the effectiveness of confirmatory anti-HBc testing and the representation of rare blood groups in anti-HBc-positive donors. MATERIALS AND METHODS: Three hundred ninety-seven HBV surface antigen-negative and anti-HBc initially reactive blood donor samples were tested by five different anti-HBc assays. RESULTS: Eighty percentage of samples reactive in Architect anti-HBc assay were positive by the Murex assay and anti-HBc neutralization. Eleven out of 397 samples showed discordant results in supplementary testing from the Murex confirmatory test result, and five remained undetermined following extensive serological testing. Thirty-eight percentage of anti-HBc-positive donors identified as minority ethnic groups compared with 11% representation in anti-HBc-negative donors (p < 0.0001); the frequency of the Ro blood group in anti-HBc-positive donors was 18 times higher in non-white ethnic groups. CONCLUSION: Using two anti-HBc assays effectively enabled the identification of HBV-exposed and potentially infectious donors, their deferral and potential clinical follow-up. However, the exclusion of confirmed anti-HBc-positive donors will still impact the supply of rare blood such as Ro.


Asunto(s)
Donantes de Sangre , Anticuerpos contra la Hepatitis B , Antígenos del Núcleo de la Hepatitis B , Virus de la Hepatitis B , Hepatitis B , Humanos , Anticuerpos contra la Hepatitis B/sangre , Hepatitis B/sangre , Hepatitis B/prevención & control , Femenino , Antígenos del Núcleo de la Hepatitis B/inmunología , Antígenos del Núcleo de la Hepatitis B/sangre , Masculino , Virus de la Hepatitis B/inmunología , Selección de Donante/métodos , Antígenos de Grupos Sanguíneos/inmunología , Donación de Sangre
17.
J Infect Dis ; 230(2): e427-e436, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-38181168

RESUMEN

BACKGROUND: Human cytomegalovirus (HCMV) is the most common and serious opportunistic infection after solid organ and hematopoietic stem cell transplantation. In this study, we used whole-genome HCMV data to investigate viral factors associated with the clinical outcome. METHODS: We sequenced HCMV samples from 16 immunocompromised pediatric patients with persistent viremia. Eight of the 16 patients died of complications due to HCMV infection. We also sequenced samples from 35 infected solid organ adult recipients, of whom 1 died with HCMV infection. RESULTS: We showed that samples from both groups have fixed variants at resistance sites and mixed infections. Next-generation sequencing also revealed nonfixed variants at resistance sites in most of the patients who died (6/9). A machine learning approach identified 10 genes with nonfixed variants in these patients. These genes formed a viral signature that discriminated patients with HCMV infection who died from those who survived with high accuracy (area under the curve = 0.96). Lymphocyte numbers for a subset of patients showed no recovery posttransplant in the patients who died. CONCLUSIONS: We hypothesize that the viral signature identified in this study may be a useful biomarker for poor response to antiviral drug treatment and indirectly for poor T-cell function, potentially identifying early those patients requiring nonpharmacological interventions.


Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , Huésped Inmunocomprometido , Humanos , Infecciones por Citomegalovirus/virología , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/mortalidad , Citomegalovirus/genética , Niño , Masculino , Femenino , Adulto , Preescolar , Antivirales/uso terapéutico , Adolescente , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Lactante , Trasplante de Órganos/efectos adversos , Secuenciación de Nucleótidos de Alto Rendimiento , Viremia , Genes Virales/genética , Variación Genética , Farmacorresistencia Viral/genética , Adulto Joven , Persona de Mediana Edad
18.
Mov Disord ; 39(2): 438-444, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38226430

RESUMEN

BACKGROUND: Although some systemic infections are associated with Parkinson's disease (PD), the relationship between herpes zoster (HZ) and PD is unclear. OBJECTIVE: The objective is to investigate whether HZ is associated with incident PD risk in a matched cohort study using data from the US Department of Veterans Affairs. METHODS: We compared the risk of PD between individuals with incident HZ matched to up to five individuals without a history of HZ using Cox proportional hazards regression. In sensitivity analyses, we excluded early outcomes. RESULTS: Among 198,099 individuals with HZ and 976,660 matched individuals without HZ (median age 67.0 years (interquartile range [IQR 61.4-75.7]); 94% male; median follow-up 4.2 years [IQR 1.9-6.6]), HZ was not associated with an increased risk of incident PD overall (adjusted HR 0.95, 95% CI 0.90-1.01) or in any sensitivity analyses. CONCLUSION: We found no evidence that HZ was associated with increased risk of incident PD in this cohort. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Herpes Zóster , Enfermedad de Parkinson , Veteranos , Humanos , Masculino , Anciano , Femenino , Estudios de Cohortes , Enfermedad de Parkinson/epidemiología , Enfermedad de Parkinson/complicaciones , Factores de Riesgo , Herpes Zóster/complicaciones , Herpes Zóster/epidemiología
19.
Clin Immunol ; 259: 109901, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38218209

RESUMEN

Chronic human norovirus (HuNoV) infections in immunocompromised patients result in severe disease, yet approved antivirals are lacking. RNA-dependent RNA polymerase (RdRp) inhibitors inducing viral mutagenesis display broad-spectrum in vitro antiviral activity, but clinical efficacy in HuNoV infections is anecdotal and the potential emergence of drug-resistant variants is concerning. Upon favipiravir (and nitazoxanide) treatment of four immunocompromised patients with life-threatening HuNoV infections, viral whole-genome sequencing showed accumulation of favipiravir-induced mutations which coincided with clinical improvement although treatment failed to clear HuNoV. Infection of zebrafish larvae demonstrated drug-associated loss of viral infectivity and favipiravir treatment showed efficacy despite occurrence of RdRp variants potentially causing favipiravir resistance. This indicates that within-host resistance evolution did not reverse loss of viral fitness caused by genome-wide accumulation of sequence changes. This off-label approach supports the use of mutagenic antivirals for treating prolonged RNA viral infections and further informs the debate surrounding their impact on virus evolution.


Asunto(s)
Amidas , Norovirus , Pirazinas , Virus , Animales , Humanos , Norovirus/genética , Antivirales/farmacología , Antivirales/uso terapéutico , Pez Cebra , Mutagénesis , ARN Polimerasa Dependiente del ARN/genética , Huésped Inmunocomprometido
20.
Emerg Infect Dis ; 30(1): 163-167, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38063078

RESUMEN

We detected a novel GII.4 variant with an amino acid insertion at the start of epitope A in viral protein 1 of noroviruses from the United States, Gabon, South Africa, and the United Kingdom collected during 2017-2022. Early identification of GII.4 variants is crucial for assessing pandemic potential and informing vaccine development.


Asunto(s)
Infecciones por Caliciviridae , Gastroenteritis , Norovirus , Humanos , Gastroenteritis/epidemiología , Norovirus/genética , Infecciones por Caliciviridae/epidemiología , Genotipo , Pandemias , Filogenia
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