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1.
BMC Ophthalmol ; 23(1): 447, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37932668

RESUMEN

Uveitis is a process of intraocular inflammation that may involve different sections of the uveal tract. Apart from systemic or localized immune-mediated diseases, infections are key players in the etiology of uveitis and entail different treatment strategies. Rubella virus (RuV) is a recognized causative agent for the development of Fuchs uveitis, representing a major cause of virus-associated intraocular inflammation. A cohort of 159 patients diagnosed with different forms of uveitis between 2013 and 2019 was subjected to diagnostic antibody testing of the aqueous or vitreous humor. The diagnostic panel included RuV, cytomegalovirus, herpes simplex virus, varicella-zoster virus, and toxoplasmosis. Within this cohort, 38 RuV-associated uveitis (RAU) patients were identified based on a pathologic Goldman-Witmer coefficient indicative of an underlying RuV infection. With a mean age of 45.9 years, the RAU patients were younger than the non-RAU patients (56.3, p < 0.001). The evaluation of clinical parameters revealed a predominance of anterior uveitis and late sequalae such as cataract and glaucoma among the RAU patients. In 15 of the patients a history of prior RuV infections could be confirmed. The study underlines the importance of long-term surveillance of RuV associated diseases that originate from infections before the introduction of RuV vaccination programs.


Asunto(s)
Infecciones Virales del Ojo , Rubéola (Sarampión Alemán) , Enfermedades de la Úvea , Uveítis Anterior , Uveítis , Humanos , Persona de Mediana Edad , Virus de la Rubéola , Centros de Atención Terciaria , Infecciones Virales del Ojo/diagnóstico , Humor Acuoso , Rubéola (Sarampión Alemán)/diagnóstico , Uveítis Anterior/diagnóstico , Inflamación
2.
Ann Hepatol ; 28(1): 100770, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36220615

RESUMEN

INTRODUCTION AND OBJECTIVES: Chronic hepatitis D infection contributes substantially to the progression of chronic liver disease, especially in most low and middle-income countries, where hepatitis B virus-related chronic liver disease is endemic. Therefore, this study aimed to determine the magnitude and genotype of hepatitis delta virus (HDV) among patients with chronic hepatitis B (CHB)-related liver diseases in Ethiopia. PATIENTS AND METHODS: In this cross-sectional study, 323 known HBsAg positive individuals comprising 220 patients with CHB-related liver diseases [121 advanced liver diseases (hepatocellular carcinoma /HCC/ and non-HCC) and 99 chronic hepatitis (CH)], and 103 symptomless blood donors (BD) were enrolled. An ELISA kit was employed to determine HDV infection, and quantitative real-time PCR was used to detect HDV RNA. In addition, a non-coding genomic RNA region was sequenced for genotyping and phylogenetic analysis. RESULTS: Irrespective of the stage of liver disease, the overall magnitude of HDV was 7.7% (25/323). The frequency of anti-HDV increases with the severity of liver disease, 1.9%, 4%, 10%, and 21.3% among BD, CH, non-HCC, and HCC patients, respectively. HDV RNA has been detected in 1.54 %(5/323) cases with a mean viral load of 4,010,360 IU/ml. All isolates were found to be HDV genotype 1. CONCLUSIONS: The magnitude of HDV infection increased with the severity of liver disease, indicating HDV infection is more common among patients with CHB-related liver diseases in Ethiopia.


Asunto(s)
Carcinoma Hepatocelular , Coinfección , Hepatitis B Crónica , Hepatitis B , Neoplasias Hepáticas , Humanos , Virus de la Hepatitis Delta/genética , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/epidemiología , Etiopía/epidemiología , Filogenia , Estudios Transversales , Virus de la Hepatitis B , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/genética , Genotipo , ARN Viral/genética , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/genética , Hepatitis B/epidemiología , Antígenos de Superficie de la Hepatitis B , Coinfección/epidemiología
3.
Virol J ; 19(1): 53, 2022 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-35331278

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) infection is a particular concern in human immunodeficiency virus (HIV) infected individuals. In Ethiopia, detailed clinical and virological descriptions of HBV prevailing during HIV co-infection and symptomatic liver disease patients are lacking. The aim of this study was to investigate HBV virological characteristics from Ethiopian HBV/HIV co-infected and HBV mono-infected individuals. METHODS: A total of 4105 sera from HIV positive individuals, liver disease patients, and blood donors were screened serologically for HBV. The overlapping polymerase/surface genome region of HBV from 180 infected individuals was extracted, amplified, and sequenced for genotypic analysis. RESULTS: The HBsAg seroprevalence was detected 43% in liver disease patients, 8.4% in blood donors, and 6.7% in HIV/HBV co-infected individuals. The occult HBV prevalence was 3.7% in HIV/HBV co-infected individuals and 2.8% in blood donors with an overall prevalence rate of 3.4%. A phylogenetic analysis showed three HBV genotypes; A (61.1%), D (38.3%) and E (0.6%). Genotype A belongs to subtypes A1 (99.1%) and A9 (0.9%), but genotype D showed heterogeneous subtypes; D2 (63.8%) followed by D4 (21.7%), D1 (8.7%), D3 (4.3%), and D10 (1.4%). CONCLUSIONS: The HIV/HBV co-infected individuals and blood donors showed lower HBsAg seroprevalence compared to liver diseases patients. Occult HBV prevalence showed no difference between HIV/HBV co-infected and blood donor groups. This study demonstrated predominance distribution of HBV subtypes A1 and D2 in northwest Ethiopia. The observed virological characteristics could contribute for evidence-based management of viral hepatitis in Ethiopia where antiretroviral therapy guidelines do not cater for viral hepatitis screening during HIV co-infection.


Asunto(s)
Coinfección , Infecciones por VIH , Hepatitis B , Coinfección/epidemiología , ADN Viral/genética , Etiopía/epidemiología , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Hepatitis B/complicaciones , Hepatitis B/epidemiología , Antígenos de Superficie de la Hepatitis B , Virus de la Hepatitis B/genética , Humanos , Epidemiología Molecular , Mutación , Filogenia , Estudios Seroepidemiológicos
4.
Arch Virol ; 167(6): 1421-1431, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35415782

RESUMEN

Human noroviruses (hNoVs) are an important cause of acute gastroenteritis worldwide. However, the lack of a reproducible in vitro cell culture system has impaired research and the development of preventive measures, therapeutic drugs, and vaccines. The aim of this study was to analyze and optimize a suitable cell line for in vitro cultivation of hNoV. The Caco-2 cell line, which is of colorectal origin and differentiates spontaneously into intestinal enterocyte-like cells, was chosen as a model. It was found that differentiated cells were more susceptible to infection with hNoV, resulting in a higher virus yield. This was accompanied by an increase in H type 1 antigen in the cell membrane during differentiation, which functions as an attachment factor for hNoV. Induced overexpression of H type 1 antigen in undifferentiated Caco-2 cells resulted in an increase in viral output to a level similar to that in differentiated cells. However, the relatively low level of viral output, which contrasts with what is observed in vivo, shows that the viral replication cycle is restricted in this model. The results indicate that there is a block at the level of viral release.


Asunto(s)
Infecciones por Caliciviridae , Gastroenteritis , Norovirus , Células CACO-2 , Técnicas de Cultivo de Célula , Humanos , Intestinos , Norovirus/genética
5.
Anal Chem ; 93(4): 2627-2634, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33471510

RESUMEN

In March 2020, the SARS-CoV-2 virus outbreak was declared as a world pandemic by the World Health Organization (WHO). The only measures for controlling the outbreak are testing and isolation of infected cases. Molecular real-time polymerase chain reaction (PCR) assays are very sensitive but require highly equipped laboratories and well-trained personnel. In this study, a rapid point-of-need detection method was developed to detect the RNA-dependent RNA polymerase (RdRP), envelope protein (E), and nucleocapsid protein (N) genes of SARS-CoV-2 based on the reverse transcription recombinase polymerase amplification (RT-RPA) assay. RdRP, E, and N RT-RPA assays required approximately 15 min to amplify 2, 15, and 15 RNA molecules of molecular standard/reaction, respectively. RdRP and E RT-RPA assays detected SARS-CoV-1 and 2 genomic RNA, whereas the N RT-RPA assay identified only SARS-CoV-2 RNA. All established assays did not cross-react with nucleic acids of other respiratory pathogens. The RT-RPA assay's clinical sensitivity and specificity in comparison to real-time RT-PCR (n = 36) were 94 and 100% for RdRP; 65 and 77% for E; and 83 and 94% for the N RT-RPA assay. The assays were deployed to the field, where the RdRP RT-RPA assays confirmed to produce the most accurate results in three different laboratories in Africa (n = 89). The RPA assays were run in a mobile suitcase laboratory to facilitate the deployment at point of need. The assays can contribute to speed up the control measures as well as assist in the detection of COVID-19 cases in low-resource settings.


Asunto(s)
COVID-19/diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Recombinasas/metabolismo , SARS-CoV-2/aislamiento & purificación , COVID-19/virología , Humanos , Sensibilidad y Especificidad
6.
Cytometry A ; 99(8): 774-783, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33280233

RESUMEN

Cytomegalovirus (CMV)-specific T cells expand with CMV reactivation and are probably prerequisite for control and protection. Given the critical role STAT5A phosphorylation (pSTAT5A) in T cell proliferation, this study presents a simple and sensitive flow cytometric-based pSTAT5A assay to quickly identify CMV-specific T cell proliferation. We determined pSTAT5A in T cells treated with CMV-specific peptide mix (pp65 + IE1 peptides) from 20 healthy adult subjects and three immunodeficient patients with CARMIL-2 mutation. After stimulation, the percentage of pSTAT5A+ T cells in CMV-seropositive (CMV+ ) subjects significantly increased from 3.0% ± 1.9% (unstimulated) to 11.4% ± 5.9% (stimulated) for 24 h. After 7 days of stimulation, the percentage of expanded T cells amounted to 26% ± 17.2%. Conversely, the percentage of pSTAT5A+ T cells and T cell proliferation from CMV-seronegative (CMV- ) subjects hardly changed (from 3.0% ± 1.3% to 3.7% ± 1.8% and from 4.3% ± 2.1% to 5.7% ± 1.7%, respectively). We analyzed the correlation between the percentage of pSTAT5A+ T cells versus (1) CMV-IgG concentrations versus (2) the percentage of expanded T cells and versus (3) the percentage of initial CMV-specific T cells. In immunodeficient patients with CARMIL-2 mutation, CMV-specific pSTAT5A and T cell proliferation were completely deficient. In conclusion, flow cytometric-based pSTAT5A assay represents an appropriate tool to quickly identify CMV-specific T cell proliferation and helps to understand dysfunctions in controlling other pathogens. Flow cytometric-based pSTAT5A assay may be a useful test in clinical practice and merits further validation in large studies.


Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , Linfocitos T CD8-positivos , Humanos , Fosfoproteínas , Fosforilación , Factor de Transcripción STAT5 , Linfocitos T , Proteínas de la Matriz Viral
7.
J Med Virol ; 92(12): 3007-3015, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32170868

RESUMEN

Enteroviruses (EVs) and human parechoviruses (HPeVs) infections are associated with various forms of disease, including gastroenteritis. As information on the molecular epidemiology of these viruses is limited in Ethiopia, the genetic diversity of EV and HPeV was investigated in the Northwestern part of the country. Of the total 450 stool samples obtained from infants and young children with diarrhea, 157 (34.9%) were positive for EV and 49 (10.9%) for HPeV RNA when tested by real-time reverse transcription polymerase chain reaction. Genotyping was performed by sequencing of the EV VP1 gene and the HPeV VP3/VP1 gene, respectively. Genotyping of EV was successful in 118 samples. Thereof, 82 (69.5%) belonged to non-polio EVs as a broad range of genotypes within species C, B, and A. Sabin polioviruses were found in 36 cases. HPeV sequences were also heterogeneous with a relative dominance of genotype 3. In conclusion, diverse EV and HPeV genotypes were found cocirculating in Northwest Ethiopia. The findings highlight the importance of continuous surveillance of these viruses in Ethiopia.

8.
Euro Surveill ; 25(46)2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33213686

RESUMEN

Following a distinct summer heat wave, nine autochthonous cases of West Nile fever and West Nile neuroinvasive disease, including one fatality, were observed in Leipzig, Germany, in August and September 2020. Phylogenetic analysis demonstrated close relationships in viruses from humans, animals and mosquitos in eastern Germany, obtained during the preceding 2 years. The described large cluster of autochthonous West Nile virus infections in Germany indicates endemic seasonal circulation of lineage 2 viruses in the area.


Asunto(s)
Brotes de Enfermedades , Fiebre del Nilo Occidental , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Alemania/epidemiología , Humanos , Persona de Mediana Edad , Filogenia , Fiebre del Nilo Occidental/epidemiología , Virus del Nilo Occidental/genética , Adulto Joven
9.
J Virol ; 92(17)2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29950419

RESUMEN

The flexible regulation of cellular metabolic pathways enables cellular adaptation to changes in energy demand under conditions of stress such as posed by a virus infection. To analyze such an impact on cellular metabolism, rubella virus (RV) was used in this study. RV replication under selected substrate supplementation with glucose, pyruvate, and glutamine as essential nutrients for mammalian cells revealed its requirement for glutamine. The assessment of the mitochondrial respiratory (based on the oxygen consumption rate) and glycolytic (based on the extracellular acidification rate) rate and capacity by respective stress tests through Seahorse technology enabled determination of the bioenergetic phenotype of RV-infected cells. Irrespective of the cellular metabolic background, RV infection induced a shift of the bioenergetic state of epithelial cells (Vero and A549) and human umbilical vein endothelial cells to a higher oxidative and glycolytic level. Interestingly there was a RV strain-specific, but genotype-independent demand for glutamine to induce a significant increase in metabolic activity. While glutaminolysis appeared to be rather negligible for RV replication, glutamine could serve as donor of its amide nitrogen in biosynthesis pathways for important metabolites. This study suggests that the capacity of RVs to induce metabolic alterations could evolve differently during natural infection. Thus, changes in cellular bioenergetics represent an important component of virus-host interactions and could complement our understanding of the viral preference for a distinct host cell population.IMPORTANCE RV pathologies, especially during embryonal development, could be connected with its impact on mitochondrial metabolism. With bioenergetic phenotyping we pursued a rather novel approach in virology. For the first time it was shown that a virus infection could shift the bioenergetics of its infected host cell to a higher energetic state. Notably, the capacity to induce such alterations varied among different RV isolates. Thus, our data add viral adaptation of cellular metabolic activity to its specific needs as a novel aspect to virus-host evolution. In addition, this study emphasizes the implementation of different viral strains in the study of virus-host interactions and the use of bioenergetic phenotyping of infected cells as a biomarker for virus-induced pathological alterations.


Asunto(s)
Metabolismo Energético , Glutamina/metabolismo , Glucólisis/efectos de los fármacos , Consumo de Oxígeno/fisiología , Virus de la Rubéola/metabolismo , Células A549 , Células Endoteliales/metabolismo , Células Endoteliales/virología , Glucosa/metabolismo , Glucosa/farmacología , Glutamina/farmacología , Homeostasis , Humanos , Quinurenina/metabolismo , Redes y Vías Metabólicas/efectos de los fármacos , Mitocondrias/metabolismo , Nucleótidos/biosíntesis , Oxidación-Reducción , Estrés Oxidativo , Consumo de Oxígeno/efectos de los fármacos , Fenotipo , Ácido Pirúvico/metabolismo , Ácido Pirúvico/farmacología , Replicación Viral/efectos de los fármacos
10.
J Virol ; 92(6)2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29263261

RESUMEN

In previous studies, we showed that the cellular RNA-binding protein AUF1 supports the replication process of the flavivirus West Nile virus. Here we demonstrate that the protein also enables effective proliferation of dengue virus and Zika virus, indicating that AUF1 is a general flavivirus host factor. Further studies demonstrated that the AUF1 isoform p45 significantly stimulates the initiation of viral RNA replication and that the protein's RNA chaperone activity enhances the interactions of the viral 5'UAR and 3'UAR genome cyclization sequences. Most interestingly, we observed that AUF1 p45 destabilizes not only the 3'-terminal stem-loop (3'SL) but also 5'-terminal stem-loop B (SLB) of the viral genome. RNA structure analyses revealed that AUF1 p45 increases the accessibility of defined nucleotides within the 3'SL and SLB and, in this way, exposes both UAR cyclization elements. Conversely, AUF1 p45 does not modulate the fold of stem-loop A (SLA) at the immediate genomic 5' end, which is proposed to function as a promoter of the viral RNA-dependent RNA polymerase (RdRp). These findings suggest that AUF1 p45, by destabilizing specific stem-loop structures within the 5' and 3' ends of the flaviviral genome, assists genome cyclization and concurrently enables the RdRp to initiate RNA synthesis. Our study thus highlights the role of a cellular RNA-binding protein inducing a flaviviral RNA switch that is crucial for viral replication.IMPORTANCE The genus Flavivirus within the Flaviviridae family includes important human pathogens, such as dengue, West Nile, and Zika viruses. The initiation of replication of the flaviviral RNA genome requires a transformation from a linear to a cyclized form. This involves considerable structural reorganization of several RNA motifs at the genomic 5' and 3' ends. Specifically, it needs a melting of stem structures to expose complementary 5' and 3' cyclization elements to enable their annealing during cyclization. Here we show that a cellular RNA chaperone, AUF1 p45, which supports the replication of all three aforementioned flaviviruses, specifically rearranges stem structures at both ends of the viral genome and in this way permits 5'-3' interactions of cyclization elements. Thus, AUF1 p45 triggers the RNA switch in the flaviviral genome that is crucial for viral replication. These findings represent an important example of how cellular (host) factors promote the propagation of RNA viruses.


Asunto(s)
Flavivirus/fisiología , Genoma Viral , Ribonucleoproteína Heterogénea-Nuclear Grupo D/metabolismo , Conformación de Ácido Nucleico , ARN Viral/metabolismo , Replicación Viral/fisiología , Ribonucleoproteína Nuclear Heterogénea D0 , Ribonucleoproteína Heterogénea-Nuclear Grupo D/química , Ribonucleoproteína Heterogénea-Nuclear Grupo D/genética , Humanos , ARN Viral/química , ARN Viral/genética , ARN Polimerasa Dependiente del ARN/química , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Proteínas Virales/química , Proteínas Virales/genética , Proteínas Virales/metabolismo
11.
Arch Virol ; 164(12): 2985-2993, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31570995

RESUMEN

Human adenovirus (HAdV) and human astrovirus (HAstV) are common causes of gastroenteritis. Data on the prevalence and diversity of enteric viruses are important for control and preventive measures. However, epidemiological information regarding HAdV and HAstV infections in Ethiopia are limited. Fecal specimens were collected from 450 outpatient diarrheic infants and young children in Gondar and Bahir Dar from November 2015 to April 2016. Socio-demographic information was recorded. All fecal specimens were screened for the presence of HAdV and classical HAstV using PCR. Genotyping was performed by sequencing and phylogenetic analysis. Human HAdV and HAstV were detected in 144 (32%) and 16 (3.6%) of the children, respectively. Overall, 182 different adenovirus genotypes were detected, including mixed infections. Species F adenoviruses (HAdV-40, HAdV-41) were less common than other adenoviruses (HAdV-1, -2, -3, -5,-12, -16, -31, species D types) with a frequency of 32 versus 150, respectively. The HAstV genotypes were classified as HAstV-8 (n = 10), HAstV-1 (n = 3), HAstV-2 (n = 3), and HAstV-3 (n = 1). HAstV was detected only in Gondar. Thirty-eight coinfections HAdV and one HAstV coinfections were detected. There was no significant difference in the detection rate of HAdV and HAstV between boys and girls. The detection rates also did not differ between children from rural and urban areas. Children under 6 months of age, were less often infected with both viruses. These findings suggest that HAdV and HAstV are common in children with diarrhea in Ethiopia.


Asunto(s)
Infecciones por Adenoviridae/virología , Adenovirus Humanos/genética , Infecciones por Astroviridae/virología , Gastroenteritis/virología , Mamastrovirus/genética , Enfermedad Aguda/epidemiología , Infecciones por Adenoviridae/epidemiología , Adenovirus Humanos/clasificación , Adenovirus Humanos/aislamiento & purificación , Adolescente , Adulto , Infecciones por Astroviridae/epidemiología , Niño , Preescolar , Etiopía/epidemiología , Femenino , Gastroenteritis/epidemiología , Variación Genética , Genotipo , Humanos , Lactante , Masculino , Mamastrovirus/clasificación , Mamastrovirus/aislamiento & purificación , Persona de Mediana Edad , Filogenia , Adulto Joven
12.
RNA ; 22(10): 1574-91, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27520967

RESUMEN

A prerequisite for the intracellular replication process of the Flavivirus West Nile virus (WNV) is the cyclization of the viral RNA genome, which enables the viral replicase to initiate RNA synthesis. Our earlier studies indicated that the p45 isoform of the cellular AU-rich element binding protein 1 (AUF1) has an RNA chaperone activity, which supports RNA cyclization and viral RNA synthesis by destabilizing a stem structure at the WNV RNA's 3'-end. Here we show that in mammalian cells, AUF1 p45 is consistently modified by arginine methylation of its C terminus. By a combination of different experimental approaches, we can demonstrate that the methyltransferase PRMT1 is necessary and sufficient for AUF1 p45 methylation and that PRMT1 is required for efficient WNV replication. Interestingly, in comparison to the nonmethylated AUF1 p45, the methylated AUF1 p45(aDMA) exhibits a significantly increased affinity to the WNV RNA termini. Further data also revealed that the RNA chaperone activity of AUF1 p45(aDMA) is improved and the methylated protein stimulates viral RNA synthesis considerably more efficiently than the nonmethylated AUF1 p45. In addition to its destabilizing RNA chaperone activity, we identified an RNA annealing activity of AUF1 p45, which is not affected by methylation. Arginine methylation of AUF1 p45 thus represents a specific determinant of its RNA chaperone activity while functioning as a WNV host factor. Our data suggest that the methylation modifies the conformation of AUF1 p45 and in this way affects its RNA binding and restructuring activities.


Asunto(s)
Arginina/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo D/metabolismo , Procesamiento Proteico-Postraduccional , ARN Viral/genética , Regiones no Traducidas 3' , Línea Celular Tumoral , Ribonucleoproteína Nuclear Heterogénea D0 , Ribonucleoproteína Heterogénea-Nuclear Grupo D/genética , Humanos , Metilación , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteína-Arginina N-Metiltransferasas/metabolismo , ARN Viral/metabolismo , Proteínas Represoras/metabolismo , Replicación Viral , Virus del Nilo Occidental/genética , Virus del Nilo Occidental/fisiología
13.
J Gen Virol ; 98(12): 3037-3045, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29095687

RESUMEN

Species D is the largest of the seven species of human mastadenoviruses (HAdV), but few of its multiple types are associated with asevere disease, e.g. epidemic keratoconjunctivitis. Many other types are hardly ever associated with significant diseases in immunocompetent patients, but have been isolated from the diarrhoeal faeces of terminal AIDS patients suggesting their role as opportunistic pathogens. Three novel HAdV-D strains were isolated from the faeces of three immunocompromised adult patients (clinical diagnoses: lymphoma, myelodysplastic syndrome and AIDS CDC3B, respectively). These strains were not typeable by imputed serology of the hexon and fibre gene and therefore complete genomic sequences were generated by next-generation sequencing (NGS). All three strains were multiple recombinants and fulfilled the criteria for designation as types 73, 74 and 75 with the penton/hexon/fibre genotype codes P67H45F27, P70H74F51 and P75H26F29, respectively. A novel genomic backbone and also a novel hexon neutralization epitope sequence were discovered in type 74, and a novel penton sequence in type 75. At the complete genome level, types 73, 74 and 75 were closely related neither to each other nor to type 70, which was previously isolated in the same region. However, these four HAdV-D types were closely related to each other in single genes and gene regions, e.g. penton, E1 and E4 due to recombination events in their phylogeny. In conclusion, regional co-circulation of opportunistic HAdV-D types facilitated co- and super-infections, which are essential for homologous recombination, and thus resulted in the evolution of novel genotypes by lateral gene transfer.

14.
Virol J ; 14(1): 176, 2017 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-28899424

RESUMEN

BACKGROUND: Although hepatitis B virus (HBV) is hyperendemic and heterogeneous in its genetic diversity in Ethiopia, little is known about hepatitis D virus (HDV) circulating genotypes and molecular diversity. METHODS: A total of 321 hepatitis B surface antigen (HBsAg) positives (125 HIV co-infected, 102 liver disease patients and 94 blood donors) were screened for anti-HDV antibody. The anti-HDV positive sera were subjected to Real time PCR for HDV-RNA confirmation. The non coding genome region (spanning from 467 to 834 nucleotides) commonly used for HDV genotyping as well as complete HDV genome were sequenced for genotyping and molecular analysis. RESULTS: The anti-HDV antibody was found to be 3.2% (3) in blood donors, 8.0% (10) in HIV co-infected individuals and 12.7% (13) in liver disease patients. None of the HIV co-infected patients who revealed HBV lamivudine (3TC) resistance at tyrosine-methionine/isoleucine-aspartate-aspartate (YM(I)DD) reverse transcriptase (RT) motif with concomitant vaccine escape gene mutants was positive for anti-HDV antibody. The HDV viremia rate was 33.3%, 30.0% and 23.1% in respect to the above study groups. All the six isolates sequenced were phylogenetically classified as HDV genotype 1 (HDV-1) and grouped into two monophyletic clusters. Amino acid (aa) residues analysis of clathrin heavy chain (CHC) domain and the isoprenylation signal site (Py) at 19 carboxyl (C)-terminal amino acids (aa 196-214) and the HDV RNA binding domain (aa 79-107) were highly conserved and showed a very little nucleotide variations. All the sequenced isolates showed serine at amino acid position 202. The RNA editing targets of the anti-genomic HDV RNA (nt1012) and its corresponding genomic RNA (nt 580) showed nucleotides A and C, respectively. CONCLUSIONS: The low seroprevalence and viraemic rates of HDV in particular during HIV-confection might be highly affected by HBV drug resistance selected HBsAg mutant variants in this setting, although HDV-1 sequences analysis revealed clade homogeneity and highly conserved structural and functional domains. Thus, the potential role of HBV drug resistance associated polymerase mutations and concomitant HBsAg protein variability on HDV viral assembly, secretion and infectivity needs further investigation.


Asunto(s)
Variación Genética , Hepatitis D/epidemiología , Hepatitis D/virología , Virus de la Hepatitis Delta/clasificación , Virus de la Hepatitis Delta/genética , Filogenia , Adulto , Coinfección , Estudios Transversales , Etiopía/epidemiología , Femenino , Genotipo , Infecciones por VIH/complicaciones , Anticuerpos Antihepatitis/sangre , Hepatitis B/complicaciones , Hepatitis B/epidemiología , Hepatitis D/complicaciones , Hepatitis D/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Análisis de Secuencia de ADN , Análisis de Secuencia de Proteína
17.
J Clin Microbiol ; 54(1): 142-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26560532

RESUMEN

Norovirus is the most common cause of sporadic gastroenteritis and outbreaks worldwide. The rapid identification of norovirus has important implications for infection prevention measures and may reduce the need for additional diagnostic testing. The Xpert Norovirus assay recently received FDA clearance for the detection and differentiation of norovirus genogroups I and II (GI and GII), which account for the vast majority of infections. In this study, we evaluated the performance of the Xpert Norovirus assay with both fresh, prospectively collected (n = 914) and frozen, archived (n = 489) fecal specimens. A Centers for Disease Control and Prevention (CDC) composite reference method was used as the gold standard for comparison. For both prospective and frozen specimens, the Xpert Norovirus assay showed positive percent agreement (PPA) and negative percent agreement (NPA) values of 98.3% and 98.1% for GI and of 99.4% and 98.2% for GII, respectively. Norovirus prevalence in the prospective specimens (collected from March to May of 2014) was 9.9% (n = 90), with the majority of positives caused by genogroup II (82%, n = 74). The positive predictive value (PPV) of the Xpert Norovirus assay was 75% for GI-positive specimens, whereas it was 86.5% for GII-positive specimens. The negative predictive values (NPV) for GI and GII were 100% and 99.9%, respectively.


Asunto(s)
Infecciones por Caliciviridae/diagnóstico , Heces/virología , Genotipo , Técnicas de Diagnóstico Molecular/métodos , Norovirus/clasificación , Norovirus/aislamiento & purificación , Virología/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Infecciones por Caliciviridae/virología , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Norovirus/genética , Valor Predictivo de las Pruebas , Estudios Prospectivos , Adulto Joven
18.
BMC Infect Dis ; 16(1): 761, 2016 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-27993129

RESUMEN

BACKGROUND: The existing seroepidemiological data on viral hepatitis in Ethiopia showed a wide variation in prevalence pattern and the clinical and public health burden have been underestimated. The aim of this systematic review and meta-analysis was to provide a clear and comprehensive estimation of viral hepatitis epidemiology and the potential clinical burdens in Ethiopia. METHODS: A comprehensive literature search was carried out from five decades (1968-2015) published studies from biomedical databases; PubMed, Google scholar, Medline and Web of Science. RESULTS: The overall pooled prevalence of hepatitis B virus (HBV) was 7.4% (95%CI: 6.5-8.4). The pooled prevalence among subgroups showed 5.2% (95%CI: 3.7-7.4) in human immunodeficiency virus (HIV) infected individuals, 8.0% (95%CI: 5.9-10.7) in community based studies, 8.4% (95%CI: 5.4-12.7) in blood donors, 11.0% (95%CI: 7.5-15.9) in immigrants and 6.9% (95%CI: 5.6-8.5) in other groups. Among study parameters considered during meta-regression analysis, only study years were associated with a decreasing HBV prevalence rate over time. The overall pooled prevalence of anti-hepatitis C virus antibody (anti-HCV) was 3.1% (95%CI: 2.2-4.4). Unlike HBV, the anti-HCV prevalence in HIV infected individuals was higher (5.5%, 95%CI: 3.8-7.8%, p = 0.01) than the prevalence observed in the other subgroup of study population. Although relatively few data were available, hepatitis virus A (HAV), D (HDV) and E (HEV) were also circulated in Ethiopia. CONCLUSIONS: This review indicates that all types of viral hepatitis origins are endemic in Ethiopia. Adapting a recommended diagnostic and treatment algorithm of viral hepatitis in the routine healthcare systems and implementing prevention and control policies in the general population needs an urgent attention.


Asunto(s)
Hepatitis Viral Humana/epidemiología , Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Adolescente , Adulto , Donantes de Sangre/estadística & datos numéricos , Coinfección/epidemiología , Etiopía/epidemiología , Infecciones por VIH/epidemiología , Infecciones por VIH/virología , Hepatitis B/epidemiología , Hepatitis B/virología , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/patogenicidad , Hepatitis C/epidemiología , Anticuerpos contra la Hepatitis C/sangre , Virus de Hepatitis/patogenicidad , Hepatitis Viral Humana/virología , Humanos , Persona de Mediana Edad , Adulto Joven
19.
Clin Oral Investig ; 20(1): 193-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26411858

RESUMEN

OBJECTIVES: Co-occurrence of oral lichen planus (OLP) and chronic hepatitis C virus (HCV) infection suggests a strong association, but the relation between mucocutaneus, autoimmune lichen planus and HCV infection remains unclear. In areas with higher prevalence of HCV infection in general population, like Japan and southern Europe, 20 to 40 % of patients with OLP test positive for anti-HCV antibodies, whereas in German populations, a co-occurrence of 4.2 to 16 % was reported. MATERIAL AND METHODS: We screened 143 patients with histopathologically proven OLP for prevalence of anti-HCV antibodies. Additionally, we examined 51 anti-HCV-positive subjects with current or past HCV infection for clinical symptoms of OLP. In all patients, confirmatory diagnosis was made by the detection of HCV RNA via reverse transcription-polymerase chain reaction (RT-PCR). A randomized control group comprised 109 blood sera samples of patients without any characteristics of OLP. RESULTS: The results of all patients showed no co-occurrence in either cohort. CONCLUSION: In conclusion, no association between oral lichen planus and chronic HCV infection in our study population was found. CLINICAL RELEVANCE: Anti-HCV antibody screening in patients with confirmed oral lichen planus is not indicated routinely in central Germany.


Asunto(s)
Hepatitis C/epidemiología , Liquen Plano Oral/epidemiología , Estudios Transversales , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa
20.
J Gen Virol ; 96(9): 2734-2742, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26002300

RESUMEN

A human mastadenovirus D (HAdV-D) isolated from diarrhoeal faeces of an allogeneic haematopoietic stem cell transplant (SCT) recipient was found to be non-typable by sequencing of loops 1 and 2 of the hexon main neutralization epitope ('imputed serology'). In contrast to HAdV-C, HAdV-D infections are rarely observed in SCT patients. Therefore, the whole genome of this isolate was sequenced and phylogenetically analysed. In addition, microneutralization testing with type-specific antisera was performed. A complete genomic sequence of 35.2 kb in length with a GC content of 57  % was obtained and found to be distantly related to HAdV-D27 (96.25 % identity). Imputed serology implicated a new type with a nucleotide sequence identity of only 96.11 % to HAdV-D37 (loop 1) and 95.76 % to HAdV-D30 and HAdV-D37 (loop 2). Microneutralization testing confirmed that this clinical isolate was not neutralized by HAdV-D37- or HAdV-D30-specific antisera. The penton base gene showed a novel sequence, which clustered with HAdV-D38, but bootscan analysis indicated an intra-penton recombination event with HAdV-D60. Another recombination event was detected within the early gene region E3 with the 12.2 kDa and CR1-α genes derived from HAdV-D58. Moreover, the E4 region was derived from HAdV-D13, but all these genes had evolved significantly from their ancestors. By contrast, the recombinant fibre gene was almost 100 % identical to HAdV-D29. In conclusion, the genomics of this novel HAdV, designated the HAdV-D70 [P70H70F29] prototype, supported the significance of multiple recombinations in the phylogeny of HAdV-D.


Asunto(s)
Infecciones por Adenoviridae/virología , Diarrea/virología , Heces/virología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Mastadenovirus/genética , Mastadenovirus/aislamiento & purificación , Complicaciones Posoperatorias/virología , Recombinación Genética , Infecciones por Adenoviridae/etiología , Genoma Viral , Humanos , Mastadenovirus/clasificación , Persona de Mediana Edad , Datos de Secuencia Molecular , Filogenia , Proteínas Virales/genética
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