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1.
J Virol ; 96(20): e0140822, 2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36214578

RESUMEN

Rotaviruses are the most common viral agents associated with foal diarrhea. Between 2014 and 2017, the annual prevalence of rotavirus in diarrheic foals ranged between 18 and 28% in Haryana (India). Whole-genome sequencing of two equine rotavirus A (ERVA) isolates (RVA/Horse-wt/IND/ERV4/2017 and RVA/Horse-wt/IND/ERV6/2017) was carried out to determine the genotypic constellations (GCs) of ERVAs. The GCs of both the isolates were G3-P[3]-I8-R3-C3-M3-A9-N3-T3-E3-H6, a unique combination reported for ERVAs so far. Both the isolates carried VP6 of genotype I8, previously unreported from equines. Upon comparison with RVAs of other species, the GC of both isolates was identical to that of a bat rotavirus strain, MSLH14, isolated from China in 2012. The nucleotide sequences of the genes encoding VP3, NSP2, and NSP3 shared >95.81% identity with bat RVA strains isolated from Africa (Gabon). The genes encoding VP1, VP2, VP7, NSP1, and NSP4 shared 94.82% to 97.12% nucleotide identities with the human strains which have zoonotic links to bats (RCH272 and MS2015-1-0001). The VP6 genes of both strains were distinct and had the highest similarity of only 87.08% with that of CMH222, a human strain of bat origin. The phylogenetic analysis and lineage studies revealed that VP7 of both isolates clustered in a new lineage (lineage X) of the G3 genotype with bat, human, and alpaca strains. Similarly, VP4 clustered in a distinct P[3] lineage. These unusual findings highlight the terra incognita of the genomic diversity of equine rotaviruses and support the need for the surveillance of RVAs in animals and humans with a "one health" approach. IMPORTANCE Rotaviruses are globally prevalent diarrheal pathogens in young animals including foals, piglets, calves, goats, sheep, cats, and dogs along with humans. The genome of rotaviruses consists of 11 segments, which enables them to undergo reshuffling by reassortment of segments from multiple species during mixed infections. In this study, the prevalence of equine rotaviruses was 32.11% in organized equine farms of North India. The complete genome analysis of two ERVA isolates revealed an unusual genomic constellation, which was previously reported only in a bat RVA strain. A segment-wise phylogenetic analysis revealed that most segments of both isolates were highly similar either to bat or to bat-like human rotaviruses. The occurrence of unusual bat-like rotaviruses in equines emphasizes the need of extensive surveillance of complete genomes of both animal and human rotaviruses with a "one health" approach.


Asunto(s)
Camélidos del Nuevo Mundo , Quirópteros , Infecciones por Rotavirus , Rotavirus , Animales , Caballos/genética , Humanos , Ovinos , Porcinos , Perros , Quirópteros/genética , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/veterinaria , Infecciones por Rotavirus/genética , Filogenia , Genoma Viral , Diarrea/veterinaria , Genotipo , Secuenciación Completa del Genoma , Camélidos del Nuevo Mundo/genética , Cabras/genética , Nucleótidos , Gabón
2.
Optom Vis Sci ; 99(3): 213-227, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35086119

RESUMEN

SIGNIFICANCE: Binocular treatment for unilateral amblyopia is an emerging treatment that requires evaluation through a randomized clinical trial. PURPOSE: This study aimed to compare change in amblyopic-eye visual acuity (VA) in children aged 4 to 6 years treated with the dichoptic binocular iPad (Apple, Cupertino, CA) game, Dig Rush (not yet commercially available; Ubisoft, Montreal, Canada), plus continued spectacle correction versus continued spectacle correction alone. METHODS: Children (mean age, 5.7 years) were randomly assigned to home treatment for 8 weeks with the iPad game (prescribed 1 h/d, 5 d/wk [n = 92], or continued spectacle correction alone [n = 90]) in a multicenter randomized clinical trial. Before enrollment, children wearing spectacles were required to have at least 16 weeks of wear or no improvement in amblyopic-eye VA (<0.1 logMAR) for at least 8 weeks. Outcome was change in amblyopic-eye VA from baseline to 4 weeks (primary) and 8 weeks (secondary) assessed by masked examiner. RESULTS: A total of 182 children with anisometropic (63%), strabismic (16%; <5∆ near, simultaneous prism and cover test), or combined-mechanism (20%) amblyopia (20/40 to 20/200; mean, 20/63) were enrolled. After 4 weeks, mean amblyopic VA improved by 1.1 logMAR lines with binocular treatment and 0.6 logMAR lines with spectacles alone (adjusted difference, 0.5 lines; 95.1% confidence interval [CI], 0.1 to 0.9). After 8 weeks, results (binocular treatment: mean amblyopic-eye VA improvement, 1.3 vs. 1.0 logMAR lines with spectacles alone; adjusted difference, 0.3 lines; 98.4% CI, -0.2 to 0.8 lines) were inconclusive because the CI included both zero and the pre-defined difference in mean VA change of 0.75 logMAR lines. CONCLUSIONS: In 4- to 6-year-old children with amblyopia, binocular Dig Rush treatment resulted in greater improvement in amblyopic-eye VA for 4 weeks but not 8 weeks. Future work is required to determine if modifications to the contrast increment algorithm or other aspects of the game or its implementation could enhance the treatment effect.


Asunto(s)
Ambliopía , Ambliopía/terapia , Niño , Preescolar , Anteojos , Estudios de Seguimiento , Humanos , Privación Sensorial , Resultado del Tratamiento , Visión Binocular
3.
Int J Surg Case Rep ; 120: 109850, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38838585

RESUMEN

INTRODUCTION AND IMPORTANCE: After strabismus surgery, infections and complications are uncommon but avoidable with the right aseptic measures. Rarely have cases of non-infectious sub-tenon abscesses been documented in the past; these cases need to be appropriately recognized and treated. CASE PRESENTATION: In this report we describe a case of bilateral sub-tenon abscess 4 weeks after medial rectus recession. Despite receiving topical antibiotics for 7 days, there was no improvement, and multiple conjunctival cultures and sensitivity showed no growth. Both eye's sub-tenon abscess was drained, irrigated with gentamicin, and the fragile suture was removed. CLINICAL DISCUSSION: Sub-tenon abscess has been associated with bacterial infection which has more sever presentation. Several facts, including the lack of organisms in the pre-operative and intraoperative cultures, the presence of big cells resembling foreign bodies, and the improvement that occurred after suture extrusion, make infection unlikely in this case. CONCLUSION: We concluded that suture reaction is most likely to be responsible for a late-onset sub-tenon abscess with a negative culture and no response to antibiotics, and the suture should be removed.

4.
Epidemiol Infect ; 140(3): 462-5, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21733265

RESUMEN

African horse sickness virus serotype 9 (AHSV-9) has been known for some time to be circulating amongst equids in West Africa without causing any clinical disease in indigenous horse populations. Whether this is due to local breeds of horses being resistant to disease or whether the AHSV-9 strains circulating are avirulent is currently unknown. This study shows that the majority (96%) of horses and donkeys sampled across The Gambia were seropositive for AHS, despite most being unvaccinated and having no previous history of showing clinical signs of AHS. Most young horses (<3 years) were seropositive with neutralizing antibodies specific to AHSV-9. Eight young equids (<3 years) were positive for AHSV-9 by serotype-specific RT-PCR and live AHSV-9 was isolated from two of these horses. Sequence analysis revealed the presence of an AHSV-9 strain showing 100% identity to Seg-2 of the AHSV-9 reference strain, indicating that the virus circulating in The Gambia was highly likely to have been derived from a live-attenuated AHSV-9 vaccine strain.


Asunto(s)
Virus de la Enfermedad Equina Africana/aislamiento & purificación , Enfermedad Equina Africana/epidemiología , Anticuerpos Antivirales/sangre , Vacunas Virales , Virus de la Enfermedad Equina Africana/clasificación , Virus de la Enfermedad Equina Africana/inmunología , Animales , Anticuerpos Neutralizantes/sangre , Equidae , Gambia/epidemiología , Caballos , ARN Viral/genética , ARN Viral/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Homología de Secuencia , Estudios Seroepidemiológicos , Serotipificación , Vacunas Atenuadas
5.
Epidemiol Infect ; 140(11): 1982-6, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22166372

RESUMEN

Prior to the recent outbreak of equine encephalosis in Israel in 2009, equine encephalosis virus (EEV) had only been isolated from equids in South Africa. In this study we show the first evidence for the circulation of EEV beyond South Africa in Ethiopia, Ghana and The Gambia, indicating that EEV is likely to be freely circulating and endemic in East and West Africa. Sequence analysis revealed that the EEV isolate circulating in The Gambia was closely related to an EEV isolate that was isolated from a horse from Israel during the EEV outbreak in 2009, indicating that the two viruses have a common ancestry. Interestingly horses in Morocco tested negative for EEV antibodies indicating that the Sahara desert may be acting as a geographical barrier to the spread to the virus to North African countries. This evidence for EEV circulation in countries in East and West Africa sheds light on how the virus may have reached Israel to cause the recent outbreak in 2009.


Asunto(s)
Enfermedades de los Caballos/epidemiología , Orbivirus/aislamiento & purificación , Infecciones por Reoviridae/veterinaria , Animales , Anticuerpos Antivirales/sangre , Secuencia de Bases , Brotes de Enfermedades/veterinaria , Ensayo de Inmunoadsorción Enzimática , Equidae , Etiopía/epidemiología , Gambia/epidemiología , Ghana/epidemiología , Enfermedades de los Caballos/virología , Caballos , Israel/epidemiología , Datos de Secuencia Molecular , Orbivirus/clasificación , Orbivirus/genética , Orbivirus/inmunología , Filogenia , ARN Viral , Infecciones por Reoviridae/epidemiología , Infecciones por Reoviridae/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estudios Seroepidemiológicos , Serotipificación
6.
Virus Genes ; 40(1): 67-75, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19830536

RESUMEN

Epizootic haemorrhagic disease virus is a 10-segmented, double-stranded RNA virus. When these ten segments of dsRNA are run on 1% agarose, eastern (Australia, Japan) and western (North America, Africa, Middle-East) strains of the virus can be separated phenotypically based on the migration of genome segments 7-9. In western strains, segments 7-9 are roughly the same size and co-migrate as a single RNA band. In eastern strains, segment 9 is smaller, so while segments 7 and 8 co-migrate, the segment 9 RNA runs faster than its western homologue. Translation experiments demonstrated that these two segment 9 homologues are both functional and produce proteins (VP6) of different sizes-something that has not been reported in any other orbivirus species to date. Sequence analysis suggests that eastern and western versions of segment 9 (VP6) have likely evolved as a response to adaptive selection in different geographical regions via gene duplication and subsequent mutation. These significant findings are considered unusual given the conserved nature of VP6 and its presumed role as the viral helicase. It is not currently known what the biological relevance of each homologue is to the virus.


Asunto(s)
Proteínas de la Cápside/genética , Evolución Molecular , Virus de la Enfermedad Hemorrágica Epizoótica/genética , Secuencia de Aminoácidos , Animales , Proteínas de la Cápside/química , Línea Celular , Secuencia Conservada , Cricetinae , Genoma Viral , Virus de la Enfermedad Hemorrágica Epizoótica/química , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia
7.
Int J Food Microbiol ; 128(3): 435-9, 2009 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-19000642

RESUMEN

Dry-cured meat production has a long tradition in Norway. However, uncontrolled mould growth on the surface of the dry-cured meat products is causing significant quality problems. As some moulds are mycotoxigenic, their growth on the dry-cured meat products could also pose a serious health risk. Such quality problems and potential health risks can be better handled if the types of moulds growing on the products are known. In total, 161 samples were collected from the ripening and packaging stages of production with the aim of identifying moulds contaminating smoked and unsmoked Norwegian dry-cured meat products. Moulds were isolated either by transferring aerial mycelium of each visible mould colonies on the products or by directly plating pieces of meat on suitable agar media. The isolates were identified at a species level by a polyphasic approach. In total, 264 isolates belonging to 20 species and four fungal genera were identified. The genus Penicillium covered 88.3% of the total isolates. This genus contributed to the isolates of smoked and unsmoked products by 91% and 84% respectively. Penicillium nalgiovense was the dominant species isolated from both smoked and unsmoked products and covered 38% of the total isolates. Penicillium solitum and P. commune were the next most frequently isolated species with a contribution of 13% and 10% respectively. Species of Cladosporium and Eurotium contributed to the total isolates by 6% and 4.9% respectively. Smoking seems to affect the growth of these dominating species differently. An increase in the isolation frequency of P. nalgiovense accompanied by the reduction in the occurrence of P. solitum, P. commune and species of Cladosporium was observed on smoked products. The survey showed that the species of Penicillium are associated with Norwegian dry-cured meat products in general. Penicillium nalgiovense, the dominating mould species, is a potential producer of penicillin and its presence could represent a threat to allergic consumers.


Asunto(s)
Cladosporium/aislamiento & purificación , Eurotium/aislamiento & purificación , Contaminación de Alimentos/análisis , Conservación de Alimentos/métodos , Productos de la Carne/microbiología , Penicillium/aislamiento & purificación , Cladosporium/clasificación , Recuento de Colonia Microbiana , Medios de Cultivo , Eurotium/clasificación , Fermentación , Microbiología de Alimentos , Noruega , Penicillium/clasificación , Filogenia , Humo , Especificidad de la Especie
8.
Res Rep Urol ; 11: 201-214, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31440484

RESUMEN

BACKGROUND: Kidney stones are considered a serious disease, due to the great discomfort that they can cause and may even lead to renal failure. Dietary habits could be the reason behind stone formation in kidneys. METHODS: Twelve kidney stone samples were collected and analyzed together with typical foodstuffs frequently consumed in the Koya area using the x-ray fluorescent technique. RESULTS: All the analyzed stones were found to be calcium-based. The results show that elements such as Ca, Zr, S and Cl can be regarded as the core elements for the formation of kidney stones in Koya city in north Iraq. CONCLUSION: Many dietary foods and drink frequently consumed by the people in Koya city were observed to contain the core elements. However, more studies are needed to demonstrate if dietary intake may be the main source for kidney stone formation.

9.
Transbound Emerg Dis ; 65(1): 235-239, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28116836

RESUMEN

Bluetongue (BT) and peste-des-petits-ruminants (PPR) are major transboundary diseases of small ruminant, which are endemic in India. Testing of bluetongue virus (BTV) and peste-des-petits-ruminants virus (PPRV) from recent outbreaks (2015-2016) in different regions of Haryana State of India revealed that 27.5% of the samples showed the presence of dual infection of BTV and PPRV. Analysis of Seg-2 of BTV (the serotype-determining protein) showed the presence of BTV-12w in several isolates. However, analysis of N gene fragment amplicons showed that viruses belong to lineage IV were most closely related to a pathogenic strain of PPRV from Delhi. This is the first report of co-circulation of PPRV lineage IV and bluetongue virus serotype 12 in the state.


Asunto(s)
Virus de la Lengua Azul/aislamiento & purificación , Lengua Azul/diagnóstico , Brotes de Enfermedades/veterinaria , Enfermedades de las Cabras/virología , Peste de los Pequeños Rumiantes/diagnóstico , Virus de la Peste de los Pequeños Rumiantes/aislamiento & purificación , Enfermedades de las Ovejas/virología , Animales , Lengua Azul/epidemiología , Lengua Azul/virología , Virus de la Lengua Azul/genética , Enfermedades de las Cabras/epidemiología , Cabras , India/epidemiología , Peste de los Pequeños Rumiantes/epidemiología , Peste de los Pequeños Rumiantes/virología , Virus de la Peste de los Pequeños Rumiantes/genética , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Ovinos , Enfermedades de las Ovejas/epidemiología
10.
J Comp Pathol ; 162: 18-28, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30060839

RESUMEN

Bluetongue virus (BTV) is neurotropic in nature, especially in ruminant fetuses and in-utero infection results in abortion and congenital brain malformations. The aim of the present study was to compare the neuropathogenicity of major Indian BTV serotypes 1, 2, 10, 16 and 23 by gross and histopathological lesions and virus distribution in experimentally infected neonatal BALB/c mice. Each BTV serotype (20 µl of inoculum containing 1 × 105 tissue culture infectious dose [TCID]50/ml of virus) was inoculated intracerebrally into 3-day-old mice, while a control group was inoculated with mock-infected cell culture medium. Infection with BTV serotypes 1, 2 and 23 led to 65-70% mortality at 7-9 days post infection (dpi) and caused severe necrotizing encephalitis with neurodegenerative changes in neurons, swelling and proliferation of vascular endothelial cells in the cerebral cortex, cerebellum, midbrain and brainstem. In contrast, infection with BTV serotypes 10 and 16 led to 25-30% mortality at 9-11 dpi and caused mild neuropathological lesions. BTV antigen was detected by immunohistochemistry, direct fluorescence antibody technique and confocal microscopy in the cytoplasm of neuronal cells of the hippocampus, grey matter of the cerebral cortex and vascular endothelial cells in the midbrain and brainstem of BTV-1, -2, -10, -16 and -23 infected groups from 3 to 20 dpi. BTV nucleic acid was detected in the infected brain tissues from as early as 24 h up to 20 dpi by VP7 gene segment-based one-step reverse transcriptase polymerase chain reaction. This study of the relative neurovirulence of BTV serotypes is likely to help design suitable vaccination and control strategies for the disease.


Asunto(s)
Lengua Azul/patología , Encéfalo/patología , Encéfalo/virología , Animales , Animales Recién Nacidos , Virus de la Lengua Azul , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos BALB C , Serogrupo
11.
Transbound Emerg Dis ; 65(2): 547-556, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29120083

RESUMEN

Bluetongue (BT) is a Culicoides-borne disease caused by several serotypes of bluetongue virus (BTV). Similar to other insect-borne viral diseases, distribution of BT is limited to distribution of Culicoides species competent to transmit BTV. In the tropics, vector activity is almost year long, and hence, the disease is endemic, with the circulation of several serotypes of BTV, whereas in temperate areas, seasonal incursions of a limited number of serotypes of BTV from neighbouring tropical areas are observed. Although BTV is endemic in all the three major tropical regions (parts of Africa, America and Asia) of the world, the distribution of serotypes is not alike. Apart from serological diversity, geography-based diversity of BTV genome has been observed, and this is the basis for proposal of topotypes. However, evolution of these topotypes is not well understood. In this study, we report the isolation and characterization of several BTV-4 isolates from India. These isolates are distinct from BTV-4 isolates from other geographical regions. Analysis of available BTV seg-2 sequences indicated that the Australasian BTV-4 diverged from African viruses around 3,500 years ago, whereas the American viruses diverged relatively recently (1,684 CE). Unlike Australasia and America, BTV-4 strains of the Mediterranean area evolved through several independent incursions. We speculate that independent evolution of BTV in different geographical areas over long periods of time might have led to the diversity observed in the current virus population.


Asunto(s)
Virus de la Lengua Azul/genética , Virus de la Lengua Azul/aislamiento & purificación , Lengua Azul/virología , Enfermedades de las Ovejas/virología , África , Animales , Asia , Australasia , Lengua Azul/epidemiología , Electroforesis en Gel de Agar/veterinaria , Geografía , India/epidemiología , Epidemiología Molecular , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Análisis de Secuencia de ADN , Serogrupo , Ovinos , Enfermedades de las Ovejas/epidemiología
12.
J Virol Methods ; 141(2): 188-97, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17241676

RESUMEN

Since 1998, six distinct serotypes of Bluetongue virus (BTV) have invaded Southern and Central Europe, persisting in some regions for up to 6 years and resulting in the deaths of >1.8 million sheep. Rapid and reliable methods of virus detection and identification play an essential part in our fight against bluetongue disease (BT). We have therefore developed and evaluated a duplex, one-step RT-PCR assay that detects genome segment 7 (encoding the major serogroup (virus-species) specific antigen and outer-core-protein VP7) from any of the 24 BTV serotypes. Although Seg-7 is highly conserved, there are sequence differences in the near terminal regions that identify two distinct phylogenetic groups. Two sets of primers (targeting Seg-7 terminal regions of viruses from these two groups) were included in a duplex RT-PCR assay system. Assay sensitivity was evaluated using tissue culture derived virus, infected vector insects and clinical samples (blood and other tissues). The assay reliably amplified Seg-7 from any of the BTV strains tested, including isolates of the 24 BTV serotypes and isolates from different geographic origins. No cross-reactions were detected with members of closely related Orbivirus species (African horsesickness virus (AHSV), Epizootic haemorrhagic disease virus (EHDV), Equine encephalosis virus (EEV) and Palyam virus (PALV)).


Asunto(s)
Virus de la Lengua Azul/aislamiento & purificación , Lengua Azul/diagnóstico , Genes Virales , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Proteínas del Núcleo Viral/genética , Animales , Lengua Azul/virología , Virus de la Lengua Azul/clasificación , Virus de la Lengua Azul/genética , Ceratopogonidae/virología , Cartilla de ADN , Insectos Vectores/virología , Sensibilidad y Especificidad , Serotipificación , Ovinos , Viremia/diagnóstico
13.
Vet World ; 10(1): 121-129, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28246456

RESUMEN

AIM: In this study, a planned research work was conducted to investigate the nutrigenomic aspects of supplementation of Allium sativum (garlic) and Ocimum sanctum (holy basil) leaf powder on the growth performance and immune characteristics of broilers. MATERIALS AND METHODS: A 6 weeks feeding trial was conducted with 280-day-old Ven Cobb broilers, distributed randomly into seven experimental groups. Each treatment had 4 replicates with 10 birds each. The birds of the control group (T1) were fed a basal diet formulated as per BIS standards. The broilers of treatment groups T2 and T3 were fed basal diet supplemented with the commercially available garlic powder (GP) at levels of 0.5% and 1.0% of the feed, respectively, while broilers in T4 and T5 were fed basal diet supplemented with commercial grade holy basil leaf powder (HBLP) at levels 0.5% and 1.0% of the feed, respectively. Birds in the T6 were fed with 0.5% GP and 0.5% HBLP, whereas T7 was fed with 1.0% GP and 1.0% HBLP. At the end of the feeding trial (6th week), blood samples were collected and analyzed for relative mRNA expression of toll-like receptors (TLR) 2, TLR 4 and TLR 7 using real-time polymerase chain reaction. RESULTS: The mean body weight gain and feed conversion efficiency were improved (p<0.05) in broilers fed the GP and HBLP incorporated diets compared with the control group. The relative mRNA expression levels of TLR 2, TLR 4 and TLR 7 in the peripheral blood of the broilers were found to be increased (p<0.05) in the birds supplemented with graded levels of the GP and HBLP as compared to the untreated group. CONCLUSION: The present work concludes that the inclusion of GP and HBLP could enhance the production performance and immune status of birds by augmenting the T-cell mediated immune response and thereby protects them from disease without decreasing growth traits as a possible substitution to conventional antimicrobials.

14.
Transbound Emerg Dis ; 64(4): 1120-1132, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26888716

RESUMEN

Epizootic haemorrhagic disease virus (EHDV) is an emerging arboviral pathogen of wild and domestic ruminants worldwide. It is closely related to bluetongue virus (BTV) and is transmitted by adult females of competent Culicoides vector species. The EHDV genome consists of ten linear double-stranded (ds)RNA segments, encoding five non-structural and seven structural proteins. Genome-segment reassortment contributes to a high level of genetic variation in individual virus strains, particularly in the areas where multiple and distinct virus lineages co-circulate. In spite of the relatively close relationship between BTV and EHDV herd-immunity to BTV does not appear to protect against the introduction and infection of animals by EHDV. Although EHDV can cause up to 80% morbidity in affected animals, vaccination with the homologous EHDV serotype is protective. Outer-capsid protein VP2, encoded by Seg-2, is the most variable of the EHDV proteins and determines both the specificity of reactions with neutralizing antibodies and consequently the identity of the eight EHDV serotypes. In contrast, VP6 (the viral helicase), encoded by Seg-9, is highly conserved, representing a virus species/serogroup-specific antigen. We report the development and evaluation of quantitative (q)RT-PCR assays targeting EHDV Seg-9 that can detect all EHDV strains (regardless of geographic origin/topotype/serotype), as well as type-specific assays targeting Seg-2 of the eight EHDV serotypes. The assays were evaluated using orbivirus isolates from the 'Orbivirus reference collection' (ORC) at The Pirbright Institute and were shown to be EHDV pan-reactive or type-specific. They can be used for rapid, sensitive and reliable detection and identification (typing) of EHDV RNA from infected blood, tissue samples, homogenized Culicoides, or tissue culture supernatant. None of the assays detected RNA from closely related but heterologous orbiviruses, or from uninfected host animals or cell cultures. The techniques presented could be used for both surveillance and vaccine matching (serotype identification) as part of control strategies for incursions in wild and domestic animal species.


Asunto(s)
Ceratopogonidae/virología , Virus de la Enfermedad Hemorrágica Epizoótica/aislamiento & purificación , Medicina Veterinaria/métodos , Proteínas Virales/genética , Animales , Reacción en Cadena de la Polimerasa/veterinaria , Infecciones por Reoviridae/diagnóstico , Infecciones por Reoviridae/veterinaria
15.
Transbound Emerg Dis ; 64(6): 1912-1917, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28004522

RESUMEN

Bluetongue is endemic in India and has been reported from most Indian states. Of late, the clinical disease is most frequently seen in the states of Andhra Pradesh, Telangana (erstwhile Andhra Pradesh state), Tamil Nadu and Karnataka. Our analysis of diagnostic samples from bluetongue outbreaks during 2010-2011 from the state of Karnataka identified bluetongue virus (BTV) serotype 5 (BTV-5) for the first time in India. One of the diagnostic samples (CH1) and subsequent virus isolate (IND2010/02) contained both BTV-2 and BTV-5. Segment 2 (seg-2) sequence data (400 bp: nucleotides 2538-2921) for IND2010/02-BTV5, showed 94.3% nucleotide identity to BTV-5 from South Africa (Accession no. AJ585126), confirming the virus serotype and also indicating that Seg-2 was derived from a Western topotype, which is in contrast to serotype 2, that belongs to an Eastern topotype. BTV-5 has been recently reported from Africa, China, French islands and the Americas. Although the exact source of the Indian BTV-5 isolate is still to be confirmed, recent identification of additional exotic serotypes in India is of real concern and might add to the severity of the disease seen in these outbreaks.


Asunto(s)
Virus de la Lengua Azul/inmunología , Lengua Azul/virología , Brotes de Enfermedades/veterinaria , Animales , Lengua Azul/epidemiología , Virus de la Lengua Azul/genética , Virus de la Lengua Azul/aislamiento & purificación , Embrión de Pollo , Coinfección/veterinaria , Cricetinae , India/epidemiología , Filogenia , Análisis de Secuencia de ADN/veterinaria , Serogrupo , Ovinos
16.
J Virol Methods ; 234: 65-74, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27054888

RESUMEN

Bluetongue virus (BTV) infects all ruminants, including cattle, goats and camelids, causing bluetongue disease (BT) that is often severe in naïve deer and sheep. Reverse-transcription-loop-mediated-isothermal-amplification (RT-LAMP) assays were developed to detect eastern or western topotype of BTV strains circulating in India. Each assay uses four primers recognizing six distinct sequences of BTV genome-segment 1 (Seg-1). The eastern (e)RT-LAMP and western (w)RT-LAMP assay detected BTV RNA in all positive isolates that were tested (n=52, including Indian BTV-1, -2, -3, -5, -9, -10, -16, -21 -23, and -24 strains) with high specificity and efficiency. The analytical sensitivity of the RT-LAMP assays is comparable to real-time RT-PCR, but higher than conventional RT-PCR. The accelerated eRT-LAMP and wRT-LAMP assays generated detectable levels of amplified DNA, down to 0.216 fg of BTV RNA template or 108 fg of BTV RNA template within 60-90min respectively. The assays gave negative results with RNA from foot-and-mouth-disease virus (FMDV), peste des petits ruminants virus (PPRV), or DNA from Capripox viruses and Orf virus (n=10), all of which can cause clinical signs similar to BT. Both RT-LAMP assays did not show any cross-reaction among themselves. The assays are rapid, easy to perform, could be adapted as a 'penside' test making them suitable for 'front-line' diagnosis, helping to identify and contain field outbreaks of BTV.


Asunto(s)
Virus de la Lengua Azul/aislamiento & purificación , Lengua Azul/diagnóstico , Enfermedades de las Cabras/diagnóstico , Técnicas de Amplificación de Ácido Nucleico/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Animales , Lengua Azul/virología , Virus de la Lengua Azul/clasificación , Virus de la Lengua Azul/genética , Bovinos , Cartilla de ADN , Genoma Viral , Enfermedades de las Cabras/virología , Cabras/virología , India , Técnicas de Amplificación de Ácido Nucleico/normas , Peste de los Pequeños Rumiantes/diagnóstico , Peste de los Pequeños Rumiantes/virología , Virus de la Peste de los Pequeños Rumiantes/genética , Virus de la Peste de los Pequeños Rumiantes/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Sensibilidad y Especificidad , Ovinos/virología , Temperatura
17.
Transbound Emerg Dis ; 63(4): 360-4, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27241307

RESUMEN

Bluetongue (BT) is a viral disease of ruminants and is caused by different serotypes of bluetongue virus (BTV), which is transmitted by several species of Culicoides midges. The disease is endemic in tropical areas, and incursions have been observed in some of the temperate areas. Twenty-seven recognized serotypes of BTV have been reported so far. Some serotype viruses have been shown to circulate in certain geographical areas. BTV-24 has been reported from Africa, the Mediterranean and the Americas, whereas it is exotic to Australasia. Here, we report isolation of BTV-24 from India and show that it has high sequence homology in genome segment 2 with other Western isolates of BTV-24. Entry of this serotype into Australasian region is a cause of concern.


Asunto(s)
Virus de la Lengua Azul/clasificación , Virus de la Lengua Azul/aislamiento & purificación , Serogrupo , Animales , Australasia/epidemiología , Lengua Azul/epidemiología , India/epidemiología
18.
Indian J Exp Biol ; 37(12): 1255-8, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10865895

RESUMEN

RT-PCR was standardised for the detection of bluetongue viral RNA using highly expressed non structural protein 1 gene as the target gene with specific primers targeted to 274 bp of 5' end of NS1 gene. PCR product was consistently obtained in 30 PCR cycles. Further, detection limit of RT-PCR was estimated using serial 10 fold dilutions of BHK 21 cells grown BTV 1. The study suggested that RT-PCR can be used for detection of BTV in Indian conditions with the sensitivity limit of 10 infectious particles of the virus. The study suggested that this technique may be used as a tool for sensitive detection of BTV in carrier/reservoir animals, insect vectors and certification of animals and their germ- plasm for export and import purposes.


Asunto(s)
Virus de la Lengua Azul/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Animales , Secuencia de Bases , Virus de la Lengua Azul/aislamiento & purificación , Línea Celular , Cricetinae , Cartilla de ADN/genética , Genes Virales , ARN Viral/análisis , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/normas , Proteínas no Estructurales Virales/genética
19.
Transbound Emerg Dis ; 61(2): 185-92, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23083078

RESUMEN

African horse sickness (AHS) is associated with high morbidity and mortality in equids, especially horses. A retrospective analysis was carried out concerning 737 AHS outbreaks that occurred during 2007-2010 in Ethiopia. A total of ten outbreaks were investigated in the study period. All four forms of the disease (pulmonary, cardiac, horse sickness fever and the combined form) were observed, with the cardiac form being the most prevalent. Multiple African horse sickness virus serotypes (AHSV-2, AHSV-4, AHSV-6, AHSV-8 and AHSV-9) were detected by molecular methods (type-specific real-time RT-PCR assays), and fourteen isolates were derived from blood and tissue samples collected during 2009-2010. This is the first report of AHSV-4, AHSV-6 or AHSV-8 in Ethiopia.


Asunto(s)
Virus de la Enfermedad Equina Africana/aislamiento & purificación , Enfermedad Equina Africana/epidemiología , Brotes de Enfermedades/veterinaria , Virosis/veterinaria , Enfermedad Equina Africana/virología , Virus de la Enfermedad Equina Africana/genética , Virus de la Enfermedad Equina Africana/inmunología , Animales , Antígenos Virales/inmunología , ADN Viral/análisis , Etiopía/epidemiología , Caballos , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Proteínas del Núcleo Viral/inmunología , Virosis/epidemiología , Virosis/virología
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