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1.
Nature ; 544(7650): 309-315, 2017 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-28405027

RESUMEN

The 2013-2016 West African epidemic caused by the Ebola virus was of unprecedented magnitude, duration and impact. Here we reconstruct the dispersal, proliferation and decline of Ebola virus throughout the region by analysing 1,610 Ebola virus genomes, which represent over 5% of the known cases. We test the association of geography, climate and demography with viral movement among administrative regions, inferring a classic 'gravity' model, with intense dispersal between larger and closer populations. Despite attenuation of international dispersal after border closures, cross-border transmission had already sown the seeds for an international epidemic, rendering these measures ineffective at curbing the epidemic. We address why the epidemic did not spread into neighbouring countries, showing that these countries were susceptible to substantial outbreaks but at lower risk of introductions. Finally, we reveal that this large epidemic was a heterogeneous and spatially dissociated collection of transmission clusters of varying size, duration and connectivity. These insights will help to inform interventions in future epidemics.


Asunto(s)
Ebolavirus/genética , Ebolavirus/fisiología , Genoma Viral/genética , Fiebre Hemorrágica Ebola/transmisión , Fiebre Hemorrágica Ebola/virología , Clima , Brotes de Enfermedades/estadística & datos numéricos , Ebolavirus/aislamiento & purificación , Geografía , Fiebre Hemorrágica Ebola/epidemiología , Humanos , Internacionalidad , Modelos Lineales , Epidemiología Molecular , Filogenia , Viaje/legislación & jurisprudencia , Viaje/estadística & datos numéricos
2.
BMC Med ; 20(1): 97, 2022 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-35197052

RESUMEN

BACKGROUND: Rapid antigen diagnostic tests (Ag-RDTs) are the most widely used point-of-care tests for detecting SARS-CoV-2 infection. Since the accuracy may have altered by changes in SARS-CoV-2 epidemiology, indications for testing, sampling and testing procedures, and roll-out of COVID-19 vaccination, we evaluated the performance of three prevailing SARS-CoV-2 Ag-RDTs. METHODS: In this cross-sectional study, we consecutively enrolled individuals aged >16 years presenting for SARS-CoV-2 testing at three Dutch public health service COVID-19 test sites. In the first phase, participants underwent either BD-Veritor System (Becton Dickinson), PanBio (Abbott), or SD-Biosensor (Roche Diagnostics) testing with routine sampling procedures. In a subsequent phase, participants underwent SD-Biosensor testing with a less invasive sampling method (combined oropharyngeal-nasal [OP-N] swab). Diagnostic accuracies were assessed against molecular testing. RESULTS: Six thousand nine hundred fifty-five of 7005 participants (99%) with results from both an Ag-RDT and a molecular reference test were analysed. SARS-CoV-2 prevalence and overall sensitivities were 13% (188/1441) and 69% (129/188, 95% CI 62-75) for BD-Veritor, 8% (173/2056) and 69% (119/173, 61-76) for PanBio, and 12% (215/1769) and 74% (160/215, 68-80) for SD-Biosensor with routine sampling and 10% (164/1689) and 75% (123/164, 68-81) for SD-Biosensor with OP-N sampling. In those symptomatic or asymptomatic at sampling, sensitivities were 72-83% and 54-56%, respectively. Above a viral load cut-off (≥5.2 log10 SARS-CoV-2 E-gene copies/mL), sensitivities were 86% (125/146, 79-91) for BD-Veritor, 89% (108/121, 82-94) for PanBio, and 88% (160/182, 82-92) for SD-Biosensor with routine sampling and 84% (118/141, 77-89) with OP-N sampling. Specificities were >99% for all tests in most analyses. Sixty-one per cent of false-negative Ag-RDT participants returned for testing within 14 days (median: 3 days, interquartile range 3) of whom 90% tested positive. CONCLUSIONS: Overall sensitivities of three SARS-CoV-2 Ag-RDTs were 69-75%, increasing to ≥86% above a viral load cut-off. The decreased sensitivity among asymptomatic participants and high positivity rate during follow-up in false-negative Ag-RDT participants emphasise the need for education of the public about the importance of re-testing after an initial negative Ag-RDT should symptoms develop. For SD-Biosensor, the diagnostic accuracy with OP-N and deep nasopharyngeal sampling was similar; adopting the more convenient sampling method might reduce the threshold for professional testing.


Asunto(s)
COVID-19 , Adolescente , Antígenos Virales/análisis , Prueba de COVID-19 , Vacunas contra la COVID-19 , Estudios Transversales , Humanos , SARS-CoV-2 , Sensibilidad y Especificidad
3.
BMC Med ; 20(1): 406, 2022 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-36280827

RESUMEN

BACKGROUND: The diagnostic accuracy of unsupervised self-testing with rapid antigen diagnostic tests (Ag-RDTs) is mostly unknown. We studied the diagnostic accuracy of a self-performed SARS-CoV-2 saliva and nasal Ag-RDT in the general population. METHODS: This large cross-sectional study consecutively included unselected individuals aged ≥ 16 years presenting for SARS-CoV-2 testing at three public health service test sites. Participants underwent molecular test sampling and received two self-tests (the Hangzhou AllTest Biotech saliva self-test and the SD Biosensor nasal self-test by Roche Diagnostics) to perform themselves at home. Diagnostic accuracy of both self-tests was assessed with molecular testing as reference. RESULTS: Out of 2819 participants, 6.5% had a positive molecular test. Overall sensitivities were 46.7% (39.3-54.2%) for the saliva Ag-RDT and 68.9% (61.6-75.6%) for the nasal Ag-RDT. With a viral load cut-off (≥ 5.2 log10 SARS-CoV-2 E-gene copies/mL) as a proxy of infectiousness, these sensitivities increased to 54.9% (46.4-63.3%) and 83.9% (76.9-89.5%), respectively. For the nasal Ag-RDT, sensitivities were 78.5% (71.1-84.8%) and 22.6% (9.6-41.1%) in those symptomatic and asymptomatic at the time of sampling, which increased to 90.4% (83.8-94.9%) and 38.9% (17.3-64.3%) after applying the viral load cut-off. In those with and without prior SARS-CoV-2 infection, sensitivities were 36.8% (16.3-61.6%) and 72.7% (65.1-79.4%). Specificities were > 99% and > 99%, positive predictive values > 70% and > 90%, and negative predictive values > 95% and > 95%, for the saliva and nasal Ag-RDT, respectively, in most analyses. Most participants considered the self-performing and result interpretation (very) easy for both self-tests. CONCLUSIONS: The Hangzhou AllTest Biotech saliva self Ag-RDT is not reliable for SARS-CoV-2 detection, overall, and in all studied subgroups. The SD Biosensor nasal self Ag-RDT had high sensitivity in individuals with symptoms and in those without prior SARS-CoV-2 infection but low sensitivity in asymptomatic individuals and those with a prior SARS-CoV-2 infection which warrants further investigation.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Estudios Transversales , Prueba de COVID-19 , Saliva , Sensibilidad y Especificidad , Antígenos Virales
4.
Emerg Infect Dis ; 25(7): 1394-1396, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31008703

RESUMEN

We evaluated the benefit of whole blood versus plasma to detect acute Zika virus infections. Comparison of Zika virus quantitative reverse transcription PCR results in single timepoint whole blood-plasma pairs from 227 patients with suspected Zika virus infection resulted in confirmation of 8 additional patients with Zika virus infection.


Asunto(s)
Pruebas Diagnósticas de Rutina , Pruebas Serológicas , Infección por el Virus Zika/diagnóstico , Infección por el Virus Zika/virología , Virus Zika , Algoritmos , Pruebas Diagnósticas de Rutina/métodos , Humanos , ARN Viral/sangre , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Pruebas Serológicas/métodos , Virus Zika/clasificación , Virus Zika/genética
5.
J Infect Dis ; 218(5): 688-697, 2018 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-29617822

RESUMEN

Background: A high genetic barrier to resistance to the integrase strand transfer inhibitor (INSTI) dolutegravir has been reported in vitro and in vivo. We describe the dynamics of INSTI resistance-associated mutations (INSTI-RAMs) and mutations in the 3'-polypurine tract (3'-PPT) in relation to virologic failure (VF) observed in the randomized Dolutegravir as Maintenance Monotherapy for HIV-1 study (DOMONO, NCT02401828). Methods: From 10 patients with VF, plasma samples were collected before the start of cART and during VF, and were used to generate Sanger sequences of integrase, the 5' terminal bases of the 3' long terminal repeat (LTR), and the 3'-PPT. Results: Median human immunodeficiency virus RNA load at VF was 3490 copies/mL (interquartile range 1440-4990 copies/mL). INSTI-RAMs (S230R, R263K, N155H, and E92Q+N155H) were detected in 4 patients, no INSTI-RAMs were detected in 4 patients, and sequencing of the integrase gene was unsuccessful in 2 patients. The time to VF ranged from 4 weeks to 72 weeks. In 1 patient, mutations developed in the highly conserved 3'-PPT. No changes in the terminal bases of the 3'-LTR were observed. Conclusions: The genetic barrier to resistance is too low to justify dolutegravir maintenance monotherapy because single INSTI-RAMs are sufficient to cause VF. The large variation in time to VF suggests that stochastic reactivation of a preexisting provirus containing a single INSTI-RAM is the mechanism for failure. Changes in the 3'-PPT point to a new dolutegravir resistance mechanism in vivo. Clinical Trials Registration: NCT02401828.


Asunto(s)
Farmacorresistencia Viral , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Inhibidores de Integrasa VIH/administración & dosificación , VIH-1/efectos de los fármacos , Compuestos Heterocíclicos con 3 Anillos/administración & dosificación , Mutación , Adulto , Femenino , VIH-1/aislamiento & purificación , Humanos , Quimioterapia de Mantención/métodos , Masculino , Persona de Mediana Edad , Oxazinas , Piperazinas , Piridonas , Ensayos Clínicos Controlados Aleatorios como Asunto , Análisis de Secuencia de ADN , Insuficiencia del Tratamiento , Carga Viral
6.
Liver Int ; 38(5): 792-796, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29285885

RESUMEN

BACKGROUND AND AIMS: Infection with Hepatitis E virus (HEV) can cause chronic liver disease in immunocompromised hosts. In transplant recipients, the use of certain immunosuppressants and food habits has been proposed as risk factors for HEV. In individuals infected with the human immunodeficiency virus (HIV), risk factors for HEV infection are less clear. We aimed to study the association between a mutation in the progesterone receptor (PR) named PROGINS and HEV-infected in HIV-positive individuals. METHODS: We evaluated the presence of the SNP PROGINS via KASP in serum samples of 64 HIV-positive individuals and 187 healthy controls. We performed ELISA tests to address the serum levels of IL-10 and IL-12, as well as T-cell stimulation assays in peripheral blood to address immune response in individuals with PROGINS. RESULTS: We found a significant association between the presence of PROGINS mutation and HEV seroprevalence in individuals infected with HIV (30% in HIV+/HEV+ versus 2% in HIV+/HEV, respectively, P = .009). Moreover, we found that HIV+/HEV+ individuals expressing the PROGINS mutation had lower serum levels of IL-10 and higher levels of IL-12. The presence of the mutation led to a reduced response upon stimulation of CD4+ and CD8+ T cells compared to those without the mutation, suggesting an immune modulation associated with PROGINS. CONCLUSIONS: Our study identified a mutation in the PR that provides significant insights into mechanisms of HEV infection in immunosuppressed individuals.


Asunto(s)
Predisposición Genética a la Enfermedad , Seropositividad para VIH/complicaciones , Hepatitis E/genética , Receptores de Progesterona/genética , Adulto , Recuento de Linfocito CD4 , Estudios de Casos y Controles , Femenino , Virus de la Hepatitis E , Humanos , Huésped Inmunocomprometido , Interleucina-10/sangre , Interleucina-12/sangre , Masculino , Persona de Mediana Edad , Mutación , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Estudios Seroepidemiológicos , Receptores de Trasplantes
7.
BMC Infect Dis ; 18(1): 251, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29859062

RESUMEN

BACKGROUND: HBsAg immune-escape mutations can favor HBV-transmission also in vaccinated individuals, promote immunosuppression-driven HBV-reactivation, and increase fitness of drug-resistant strains. Stop-codons can enhance HBV oncogenic-properties. Furthermore, as a consequence of the overlapping structure of HBV genome, some immune-escape mutations or stop-codons in HBsAg can derive from drug-resistance mutations in RT. This study is aimed at gaining insight in prevalence and characteristics of immune-associated escape mutations, and stop-codons in HBsAg in chronically HBV-infected patients experiencing nucleos(t)ide analogues (NA) in Europe. METHODS: This study analyzed 828 chronically HBV-infected European patients exposed to ≥ 1 NA, with detectable HBV-DNA and with an available HBsAg-sequence. The immune-associated escape mutations and the NA-induced immune-escape mutations sI195M, sI196S, and sE164D (resulting from drug-resistance mutation rtM204 V, rtM204I, and rtV173L) were retrieved from literature and examined. Mutations were defined as an aminoacid substitution with respect to a genotype A or D reference sequence. RESULTS: At least one immune-associated escape mutation was detected in 22.1% of patients with rising temporal-trend. By multivariable-analysis, genotype-D correlated with higher selection of ≥ 1 immune-associated escape mutation (OR[95%CI]:2.20[1.32-3.67], P = 0.002). In genotype-D, the presence of ≥ 1 immune-associated escape mutations was significantly higher in drug-exposed patients with drug-resistant strains than with wild-type virus (29.5% vs 20.3% P = 0.012). Result confirmed by analysing drug-naïve patients (29.5% vs 21.2%, P = 0.032). Strong correlation was observed between sP120T and rtM204I/V (P < 0.001), and their co-presence determined an increased HBV-DNA. At least one NA-induced immune-escape mutation occurred in 28.6% of patients, and their selection correlated with genotype-A (OR[95%CI]:2.03[1.32-3.10],P = 0.001). Finally, stop-codons are present in 8.4% of patients also at HBsAg-positions 172 and 182, described to enhance viral oncogenic-properties. CONCLUSIONS: Immune-escape mutations and stop-codons develop in a large fraction of NA-exposed patients from Europe. This may represent a potential threat for horizontal and vertical HBV transmission also to vaccinated persons, and fuel drug-resistance emergence.


Asunto(s)
Antivirales/uso terapéutico , Codón de Terminación , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/inmunología , Mutación , Adulto , Sustitución de Aminoácidos , Europa (Continente) , Femenino , Genotipo , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad
8.
J Hepatol ; 66(5): 1082-1095, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27913223

RESUMEN

Hepatitis E virus (HEV) infections are not limited to the liver but may also affect other organs. Several diseases, including Guillain-Barré syndrome, neuralgic amyotrophy, glomerulonephritis, cryoglobulinemia, pancreatitis, lymphoma, thrombopenia, meningitis, thyroiditis and myocarditis have been observed in the context of hepatitis E. To date, the definite pathophysiological links between HEV and extrahepatic manifestations are not yet established. However, it is suggested that HEV infection might be causative based on serological studies, case series, in vitro data and animal models. In particular, neuronal and renal diseases as well as pancreatitis seem to be caused by HEV, while a causative relationship between HEV and other diseases is more doubtful. Either direct cytopathic tissue damage by extrahepatic replication, or immunological processes induced by an overwhelming host immune response, are possible origins of HEV-associated extrahepatic manifestations. Hepatologists should be aware of the possibility that acute or chronically HEV-infected patients could develop extrahepatic manifestations. Neurologists, nephrologists, rheumatologists and other groups of physicians should consider HEV infection as a potential differential diagnosis when observing one of the diseases described in this review. Ribavirin and steroids have been used in small groups of patients with extrahepatic manifestations of HEV, but the efficacy of these drugs still needs to be verified by large, multicenter studies. This article comprehensively reviews the published literature regarding HEV and extrahepatic manifestations. We discuss the probability of specific extrahepatic diseases being caused by previous or ongoing HEV infection, and summarize the published knowledge about antiviral treatment in extrahepatic disorders.


Asunto(s)
Hepatitis E/complicaciones , Animales , Neuritis del Plexo Braquial/etiología , Síndrome de Guillain-Barré/etiología , Hepatitis Autoinmune/etiología , Humanos , Enfermedades Renales/etiología , Trastornos Mentales/etiología , Gammopatía Monoclonal de Relevancia Indeterminada/etiología , Pancreatitis/etiología , Trombocitopenia/etiología
9.
J Gen Virol ; 98(6): 1294-1298, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28597817

RESUMEN

Patients in high-risk groups continue to transmit the hepatitis C virus (HCV) and frequently experience reinfections. Since little is known regarding the immune response to HCV during reinfection, we compared primary and consecutive acute HCV infections in patients with an HIV infection, and focused on the cytokine bridging innate to adaptive immunity. We observed that the serum levels of IL-12p40, MIP-1ß, MIG and IP-10 increased during primary acute HCV infection, but not during subsequent secondary acute reinfections. The weaker pro-inflammatory cytokine responses observed during HCV reinfections suggest more limited secondary acute immune responses, which may prevent damage to the infected liver.


Asunto(s)
Coinfección/inmunología , Citocinas/sangre , Infecciones por VIH/complicaciones , Hepacivirus/inmunología , Hepatitis C/complicaciones , Hepatitis C/inmunología , Inmunidad Adaptativa , Coinfección/patología , Hepatitis C/patología , Humanos , Inmunidad Innata , Recurrencia , Estudios Retrospectivos
10.
J Virol ; 90(9): 4394-401, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26889028

RESUMEN

UNLABELLED: Genotype 3 (gt3) hepatitis E virus (HEV) infections are emerging in Western countries. Immunosuppressed patients are at risk of chronic HEV infection and progressive liver damage, but no adequate model system currently mimics this disease course. Here we explore the possibilities of in vivo HEV studies in a human liver chimeric mouse model (uPA(+/+)Nod-SCID-IL2Rγ(-/-)) next to the A549 cell culture system, using HEV RNA-positive EDTA-plasma, feces, or liver biopsy specimens from 8 immunocompromised patients with chronic gt3 HEV. HEV from feces- or liver-derived inocula showed clear virus propagation within 2 weeks after inoculation onto A549 cells, compared to slow or no HEV propagation of HEV RNA-positive, EDTA-plasma samples. These in vitro HEV infectivity differences were mirrored in human-liver chimeric mice after intravenous (i.v.) inoculation of selected samples. HEV RNA levels of up to 8 log IU HEV RNA/gram were consistently present in 100% of chimeric mouse livers from week 2 to week 14 after inoculation with human feces- or liver-derived HEV. Feces and bile of infected mice contained moderate to large amounts of HEV RNA, while HEV viremia was low and inconsistently detected. Mouse-passaged HEV could subsequently be propagated for up to 100 days in vitro In contrast, cell culture-derived or seronegative EDTA-plasma-derived HEV was not infectious in inoculated animals. In conclusion, the infectivity of feces-derived human HEV is higher than that of EDTA-plasma-derived HEV both in vitro and in vivo Persistent HEV gt3 infections in chimeric mice show preferential viral shedding toward mouse bile and feces, paralleling the course of infection in humans. IMPORTANCE: Hepatitis E virus (HEV) genotype 3 infections are emerging in Western countries and are of great concern for immunosuppressed patients at risk for developing chronic HEV infection. Lack of adequate model systems for chronic HEV infection hampers studies on HEV infectivity and transmission and antiviral drugs. We compared the in vivo infectivity of clinical samples from chronic HEV patients in human liver chimeric mice to an in vitro virus culture system. Efficient in vivo HEV infection is observed after inoculation with feces- and liver-derived HEV but not with HEV RNA-containing plasma or cell culture supernatant. HEV in chimeric mice is preferentially shed toward bile and feces, mimicking the HEV infection course in humans. The observed in vivo infectivity differences may be relevant for the epidemiology of HEV in humans. This novel small-animal model therefore offers new avenues to unravel HEV's pathobiology.


Asunto(s)
Genotipo , Virus de la Hepatitis E/genética , Hepatitis E/virología , Animales , Línea Celular , Enfermedad Crónica , Modelos Animales de Enfermedad , Virus de la Hepatitis E/metabolismo , Hepatocitos/trasplante , Hepatocitos/virología , Interacciones Huésped-Patógeno , Humanos , Ratones , Carga Viral , Replicación Viral
11.
Euro Surveill ; 22(11)2017 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-28333617

RESUMEN

A Dutch traveller returning from Suriname in early March 2017, presented with fever and severe acute liver injury. Yellow fever was diagnosed by (q)RT-PCR and sequencing. During hospital stay, the patient's condition deteriorated and she developed hepatic encephalopathy requiring transfer to the intensive care. Although yellow fever has not been reported in the last four decades in Suriname, vaccination is recommended by the World Health Organization for visitors to this country.


Asunto(s)
Insectos Vectores/virología , Viaje , Fiebre Amarilla/diagnóstico , Virus de la Fiebre Amarilla/aislamiento & purificación , Adulto , Animales , Antibacterianos/uso terapéutico , Doxiciclina/uso terapéutico , Femenino , Humanos , Mordeduras y Picaduras de Insectos , Países Bajos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Suriname , Resultado del Tratamiento , Fiebre Amarilla/sangre , Fiebre Amarilla/tratamiento farmacológico , Virus de la Fiebre Amarilla/genética
12.
J Med Virol ; 88(6): 1035-43, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26629781

RESUMEN

Although hepatitis B virus (HBV) infection is hyperendemic in Ethiopia and constitutes a major public health problem, little is known about its genetic diversity, genotypes, and circulation. The aim of this study was to determine the molecular epidemiology and genetic diversity of HBV in Ethiopia, using 391 serum samples collected from HBsAg-positive blood donors living in five different geographic regions. The HBV S/pol gene was amplified, sequenced, and HBV genotypes, subgenotypes, serotypes, and major hydrophilic region (MHR) variants were determined. Phylogenetic analysis of 371 samples (95%) revealed the distribution of genotypes A (78%) and D (22%) in Ethiopia. Further phylogenetic analysis identified one subgenotype (A1) within genotype A, and 4 subgenotypes within genotype D (D1; 1.3%, D2; 55%, D4; 2.5%, and D6; 8.8%). Importantly, 24 isolates (30%) of genotype D formed a novel phylogenetic cluster, distinct from any known D subgenotypes, and two A/D recombinants. Analysis of predicted amino-acid sequences within the HBsAg revealed four serotypes: adw2 (79%), ayw1 (3.1%), ayw2 (7.8%), and ayw3 (11.6%). Subsequent examination of sequences showed that 51 HBV isolates (14%) had mutations in the MHR and 8 isolates (2.2%) in the reverse transcriptase known to confer antiviral resistance. This study provides the first description of HBV genetic diversity in Ethiopia with a predominance of subgenotypes A1 and D2, and also identified HBV isolates that could represent a novel subgenotype. Furthermore, a significant prevalence of HBsAg variants in Ethiopian population is revealed.


Asunto(s)
Variación Genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/epidemiología , Hepatitis B Crónica/virología , Hepatitis B/epidemiología , Hepatitis B/virología , Adolescente , Adulto , Secuencia de Aminoácidos , Anticuerpos Antivirales/sangre , Secuencia de Bases , ADN Viral/sangre , Etiopía/epidemiología , Femenino , Genotipo , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/genética , Humanos , Masculino , Persona de Mediana Edad , Mutación , Filogenia , Prevalencia , Análisis de Secuencia de ADN , Serogrupo , Adulto Joven
13.
Hepatology ; 62(1): 87-100, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25808668

RESUMEN

UNLABELLED: To identify immunological mechanisms that govern distinct clinical phases of a chronic hepatitis B virus (HBV) infection-immune tolerant (IT), immune active (IA), inactive carrier (IC), and hepatitis B e antigen (HBeAg)-negative (ENEG) hepatitis phases-we performed a systems biology study. Serum samples from untreated chronic HBV patients (n = 71) were used for multiplex cytokine measurements, quantitative hepatitis B surface antigen (HBsAg), HBeAg levels, HBV genotype, and mutant analysis. Leukocytes were phenotyped using multicolor flow cytometry, and whole-blood transcriptome profiles were generated. The latter were compared with liver biopsy transcriptomes from IA (n = 16) and IT (n = 3) patients. HBV viral load as well as HBeAg and HBsAg levels (P < 0.001), but not leukocyte composition, differed significantly between distinct phases. Serum macrophage chemotactic protein 1, interleukin-12p40, interferon (IFN)-gamma-inducible protein 10, and macrophage inflammatory protein 1 beta levels were different between two or more clinical phases (P < 0.05). Comparison of blood transcriptomes identified 64 differentially expressed genes. The gene signature distinguishing IA from IT and IC patients was predominantly composed of highly up-regulated immunoglobulin-encoding genes. Modular repertoire analysis using gene sets clustered according to similar expression patterns corroborated the abundant expression of B-cell function-related genes in IA patients and pointed toward increased (ISG) transcript levels in IT patients, compared to subsequent phases. Natural killer cell activities were clustered in clinical phases with biochemical liver damage (IA and ENEG phases), whereas T-cell activities were higher in all phases, compared to IT patients. B-cell-related transcripts proved to be higher in biopsies from IA versus IT patients. CONCLUSION: HBV clinical phases are characterized by distinct blood gene signatures. Innate IFN and B-cell responses are highly active during the IT and IA phases, respectively. This suggests that the presumed immune tolerance in chronic HBV infections needs to be redefined.


Asunto(s)
Perfilación de la Expresión Génica , Hepatitis B Crónica/sangre , Hepatitis B Crónica/inmunología , Transcriptoma , Adulto , Citocinas/sangre , Femenino , Citometría de Flujo , Hepatitis B/genética , Humanos , Inmunidad Innata , Inmunofenotipificación , Masculino , Persona de Mediana Edad , Biología de Sistemas , Proteínas del Núcleo Viral/genética , Adulto Joven
14.
Bull World Health Organ ; 94(12): 880-892, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27994281

RESUMEN

OBJECTIVE: To examine the diagnostic performance of real-time reverse transcription (RT)-polymerase chain reaction (PCR) assays for Zika virus detection. METHODS: We compared seven published real-time RT-PCR assays and two new assays that we have developed. To determine the analytical sensitivity of each assay, we constructed a synthetic universal control ribonucleic acid (uncRNA) containing all of the assays' target regions on one RNA strand and spiked human blood or urine with known quantities of African or Asian Zika virus strains. Viral loads in 33 samples from Zika virus-infected patients were determined by using one of the new assays. FINDINGS: Oligonucleotides of the published real-time RT-PCR assays, showed up to 10 potential mismatches with the Asian lineage causing the current outbreak, compared with 0 to 4 mismatches for the new assays. The 95% lower detection limit of the seven most sensitive assays ranged from 2.1 to 12.1 uncRNA copies/reaction. Two assays had lower sensitivities of 17.0 and 1373.3 uncRNA copies/reaction and showed a similar sensitivity when using spiked samples. The mean viral loads in samples from Zika virus-infected patients were 5 × 104 RNA copies/mL of blood and 2 × 104 RNA copies/mL of urine. CONCLUSION: We provide reagents and updated protocols for Zika virus detection suitable for the current outbreak strains. Some published assays might be unsuitable for Zika virus detection, due to the limited sensitivity and potential incompatibility with some strains. Viral concentrations in the clinical samples were close to the technical detection limit, suggesting that the use of insensitive assays will cause false-negative results.


Asunto(s)
Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Infección por el Virus Zika/diagnóstico , Humanos , Sensibilidad y Especificidad
15.
Euro Surveill ; 21(39)2016 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-27719751

RESUMEN

The Dutch virus-typing network VIRO-TypeNed reported an increase in ECHOvirus 6 (E-6) infections with neurological symptoms in the Netherlands between June and August 2016. Of the 31 cases detected from January through August 2016, 15 presented with neurological symptoms. Ten of 15 neurological cases were detected in the same province and the identified viruses were genetically related. This report is to alert medical and public health professionals of the circulation of E-6 associated with neurological symptoms.


Asunto(s)
Brotes de Enfermedades , Echovirus 6 Humano/aislamiento & purificación , Infecciones por Echovirus/epidemiología , Meningitis Aséptica/epidemiología , Meningitis Aséptica/virología , Vigilancia de la Población/métodos , Salud Pública , Adolescente , Adulto , Líquido Cefalorraquídeo/virología , Niño , Preescolar , Sistemas de Información en Laboratorio Clínico , Echovirus 6 Humano/genética , Infecciones por Echovirus/diagnóstico , Infecciones por Echovirus/virología , Humanos , Persona de Mediana Edad , Países Bajos/epidemiología , Filogenia , Adulto Joven
16.
Euro Surveill ; 21(39)2016 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-27719752

RESUMEN

VIRO-TypeNed is a collaborative molecular surveillance platform facilitated through a web-based database. Genetic data in combination with epidemiological, clinical and patient data are shared between clinical and public health laboratories, as part of the surveillance underpinning poliovirus eradication. We analysed the combination of data submitted from 2010 to 2014 to understand circulation patterns of non-polio enteroviruses (NPEV) of public health relevance. Two epidemiological patterns were observed based on VIRO-TypeNed data and classical surveillance data dating back to 1996: (i) endemic cyclic, characterised by predictable upsurges/outbreaks every two to four years, and (ii) epidemic, where rare virus types caused upsurges/outbreaks. Genetic analysis suggests continuous temporal displacement of virus lineages due to the accumulation of (silent) genetic changes. Non-synonymous changes in the antigenic B/C loop suggest antigenic diversification, which may affect population susceptibility. Infections were frequently detected at an age under three months and at an older, parenting age (25-49 years) pointing to a distinct role of immunity in the circulation patterns. Upsurges were detected in the summer and winter which can promote increased transmissibility underlying new (cyclic) upsurges and requires close monitoring. The combination of data provide a better understanding of NPEV circulation required to control and curtail upsurges and outbreaks.


Asunto(s)
Sistemas de Información en Laboratorio Clínico , Bases de Datos de Ácidos Nucleicos , Infecciones por Enterovirus/epidemiología , Enterovirus/genética , Laboratorios , Vigilancia de la Población/métodos , Brotes de Enfermedades/prevención & control , Enfermedades Endémicas , Enterovirus/aislamiento & purificación , Infecciones por Enterovirus/diagnóstico , Infecciones por Enterovirus/virología , Epidemias , Humanos , Datos de Secuencia Molecular , Países Bajos/epidemiología , Salud Pública , Serotipificación
17.
Euro Surveill ; 21(48)2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27934581

RESUMEN

In October 2016, a severe infection with swine influenza A(H1N1) virus of the Eurasian avian lineage occurred in a child with a previous history of eczema in the Netherlands, following contact to pigs. The patient's condition deteriorated rapidly and required life support through extracorporeal membrane oxygenation. After start of oseltamivir treatment and removal of mucus plugs, the patient fully recovered. Monitoring of more than 80 close unprotected contacts revealed no secondary cases.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/diagnóstico , Infecciones del Sistema Respiratorio/virología , Síndrome Respiratorio Agudo Grave/terapia , Animales , Antivirales/uso terapéutico , Humanos , Gripe Humana/tratamiento farmacológico , Gripe Humana/virología , Unidades de Cuidado Intensivo Pediátrico , Países Bajos , Infecciones por Orthomyxoviridae/transmisión , Infecciones por Orthomyxoviridae/veterinaria , Infecciones por Orthomyxoviridae/virología , Oseltamivir/uso terapéutico , Reacción en Cadena en Tiempo Real de la Polimerasa , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Síndrome Respiratorio Agudo Grave/complicaciones , Porcinos , Enfermedades de los Porcinos/transmisión , Enfermedades de los Porcinos/virología , Resultado del Tratamiento
19.
J Med Virol ; 87(3): 472-7, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25196311

RESUMEN

Adenoviruses are a common cause of conjunctivitis. Genotypes are diverse and differ according to population and geographical distribution of the virus. There is limited data regarding ocular adenoviral infections and genotype distribution in Turkey. This study aimed to determine the adenovirus genotypes and their epidemiological features among patients with conjunctivitis between 2006 and 2010, in Izmir, Turkey. Adenoviral DNA was detected by PCR in 213 of 488 (44%) of the ocular samples collected from patients with viral conjunctivitis during the 5-year study period. Of these, 101 (47%) were randomly chosen and genotyped by sequence analysis. Seven genotypes were identified, including 3, 4, 8, 11, 19, 37, and 53. Genotype 8 and 4 were the dominant types detected in 67 (66.3%) and 25 (24.7%) of the samples, respectively. Other five genotypes (3, 11, 19, 37, 53) were detected in 9 (8.9%) samples. Genotype and seasonal differences observed throughout the study. Human adenoviruse (HAdV)-8 was the most frequent type, except 2008. The prevalence of genotype 4 increased starting from 2006, became dominant in 2008 and decreased in the following years. The peak season was mostly spring months, although it was possible to detect positive samples throughout the year. In conclusion, genotype 8 followed by genotype 4 was the most frequent adenoviral types causing conjunctivitis during the 5-year study period. Findings suggest that there is a slow shift between genotypes throughout the years.


Asunto(s)
Infecciones por Adenoviridae/epidemiología , Infecciones por Adenoviridae/virología , Adenoviridae/clasificación , Adenoviridae/aislamiento & purificación , Conjuntivitis Viral/epidemiología , Conjuntivitis Viral/virología , Adenoviridae/genética , ADN Viral/genética , Genotipo , Humanos , Reacción en Cadena de la Polimerasa , Prevalencia , Estaciones del Año , Análisis de Secuencia de ADN , Turquía/epidemiología
20.
Blood ; 122(6): 1079-86, 2013 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-23794068

RESUMEN

Hepatitis E virus (HEV) is increasingly acknowledged as a cause of hepatitis in healthy individuals as well as immunocompromised patients. Little is known of HEV infection in recipients of allogeneic hematopoietic stem cell transplantation (alloHSCT). Therefore, we set out to study the incidence and sequelae of HEV as a cause of hepatitis in a recent cohort of 328 alloHSCT recipients. HEV RNA was tested in episodes of liver enzyme abnormalities. In addition, HEV RNA and HEV serology were assessed pre- and post-alloHSCT. We found 8 cases (2.4%) of HEV infection, of which 5 had developed chronic HEV infection. Seroprevalence pre-alloHSCT was 13%. Four patients died with HEV viremia, with signs of ongoing hepatitis, having a median time of infection of 4.1 months. The 4 surviving patients cleared HEV after a median period of 6.3 months. One patient was diagnosed with HEV reactivation after a preceding infection prior to alloHSCT. Although the incidence of developing acute HEV post-alloHSCT is relatively low, the probability of developing chronic hepatitis in severely immunocompromised patients is high. Therefore, alloHSCT recipients should be screened pretransplantation by HEV serology and RNA. Furthermore, a differential diagnosis including hepatitis E is mandatory in all alloHSCT patients with severe liver enzyme abnormalities.


Asunto(s)
Neoplasias Hematológicas/complicaciones , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Virus de la Hepatitis E/aislamiento & purificación , Hepatitis E/complicaciones , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/virología , Humanos , Huésped Inmunocomprometido , Hígado/enzimología , Masculino , Persona de Mediana Edad , ARN Viral/aislamiento & purificación , Estudios Retrospectivos , Estudios Seroepidemiológicos , Trasplante Homólogo , Resultado del Tratamiento , Adulto Joven
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