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1.
Microbiol Resour Announc ; 13(4): e0125523, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38501774

RESUMEN

Here, we report the identification and coding-complete genome sequence of a severe acute respiratory syndrome COVID-19 (SARS-CoV-2) strain obtained from a Moroccan patient. The detected strain EF.1 belongs to the BQ1.1 subvariant of the BA.5 Omicron variant.

2.
Microbiol Resour Announc ; 12(6): e0007723, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37222607

RESUMEN

Here, we present the complete coding sequences of two severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains that were recovered from a nasopharyngeal swab from a female patient and the second viral passage in cell culture. After testing, both strains were identified as BA.5.2.20, a subvariant of Omicron.

3.
Afr Health Sci ; 23(3): 400-405, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38357173

RESUMEN

Background: The SARS-CoV-2 is an extremely contagious and acute viral disease mainly affecting humans. Objective: To estimate seroprevalence of SARS-CoV-2 neutralizing antibodies (NAbs) for illegible armed force individuals living in Rabat, Morocco. Method: A convenience sample (N = 2662) was conducted from May 2020 to February 2021. We used the standard neutralization assay to quantify the NAbs titers. A serum was positive when the titer was 1:4. High positive NAbs titers were defined when ≥ 1:32. Results: Demographic and socioeconomic status did not affect seroprevalence data. An overall seroprevalence of 24,9% was found. Sera from blood donors, young recruits and auto-immune population had lower NAbs titers. However, titers were above 1:16 in 9% of the population with high risk of SARS-CoV-2 exposure. Seropositivity increased over time with values reaching peaks after the epidemic waves (2.4% in May 2020; 16.2% in August 2020; 22.7% in December 2020 and 37% in February 2021). Conclusion: And increase of NAbs was observed over time and correlated with the post-epidemic waves of COVID-19 in Morocco.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiología , Marruecos/epidemiología , Estudios Seroepidemiológicos , Anticuerpos Neutralizantes , Anticuerpos Antivirales
4.
Microbiol Resour Announc ; 11(5): e0006322, 2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35420465

RESUMEN

Here, we describe the coding-complete sequence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain HM36, identified as a strain of concern of B.1.1.529+BA (Omicron).

5.
Microbiol Resour Announc ; 11(2): e0109921, 2022 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-35112895

RESUMEN

We report here the complete genome sequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains obtained from Moroccan patients with COVID-19. The analysis of these sequences indicates that the identified strains belong to the AY.33 sublineage of the Delta variant.

6.
Biosens Bioelectron ; 199: 113868, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34920226

RESUMEN

COVID-19 vaccination efficacy depends on serum levels of the neutralizing antibodies (NAs) specific to the receptor-binding domain of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. Therefore, a high-throughput rapid assay capable of measuring the total SARS-CoV-2 NA level is urgently needed for COVID-19 serodiagnosis, convalescent plasma therapy, vaccine development, and assessment. Here, we developed a novel nanoplasmonic immunosorbent assay (NanoPISA) platform for one-step rapid quantification of SARS-CoV-2 NAs in clinical serum samples for high-throughput evaluation of COVID-19 vaccine effectiveness. The NanoPISA platform enhanced by the use of nanoporous hollow gold nanoparticle coupling was able to detect SARS-CoV-2 NAs with a limit of detection of 0.2 pM within 15 min without washing steps. The one-step NanoPISA for SARS-CoV-2 NA detection in clinical specimens yielded good results, comparable with those obtained in the gold-standard seroneutralization test and the surrogate virus-neutralizing enzyme-linked immunosorbent assay. Collectively, the one-step NanoPISA might be a rapid and high-throughput NA-quantification platform for evaluating the effectiveness of COVID-19 vaccines.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Nanopartículas del Metal , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/terapia , Vacunas contra la COVID-19 , Oro , Humanos , Inmunización Pasiva , SARS-CoV-2 , Vacunación , Desarrollo de Vacunas , Eficacia de las Vacunas , Sueroterapia para COVID-19
7.
Microbiol Resour Announc ; 10(39): e0072721, 2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34591666

RESUMEN

Here, we report the identification and coding-complete genome sequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains obtained from patients with COVID-19. The strains identified belong to variant of concern B.1.617.2 and variant of interest B.1.617.1.

8.
Germs ; 11(2): 189-198, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34422691

RESUMEN

INTRODUCTION: Escherichia coli is the most commonly isolated species in both community and healthcare-associated infections. Our study's purpose was to determine the rates of antibiotic resistance of E. coli isolates in hospital and community populations, track the kinetics of resistance rates of E. coli isolates to major antibiotics, particularly those prescribed for urinary tract infections and study the occurrence and evolution of multi-resistant phenotypes. METHODS: We conducted a retrospective study at the Bacteriological Department of the Mohammed V Military Hospital of Instruction, over a period of 7 years. All isolates of E. coli from inpatients and outpatients were included. Identification of bacterial isolates was based on culture, morphological and biochemical identification characteristics. Antibiotic susceptibility was studied using the Mueller Hilton agar diffusion method by using OXOID® type antibiotic discs and interpreted according to the recommendations of EUCAST/CA-SFM 2019. RESULTS: The rate of resistance of E. coli isolates to 3rd generation cephalosporins, imipenem and fluoroquinolones was 12%, 1% and 34%, respectively. The difference between the resistance rates of inpatient and outpatient E. coli isolates was statistically significant for most antibiotics (p<0.05). The rate of extended-spectrum beta-lactamase phenotype (ESBL) was 6.73%. The carbapenemase phenotype was 1.25%. The ESBL phenotype rate increased from 3% in 2012 to 11.16% in 2018. CONCLUSIONS: The progression of the ESBL phenotype in both hospital and community settings, due to the increase in the resistance rate to 3rd generation cephalosporin, is prompting a review of the strategy for the therapeutic management of urinary tract infections with these molecules as probabilistic treatment.

9.
Microbiol Resour Announc ; 10(20)2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-34016683

RESUMEN

The complete genome sequence of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain was obtained. The strain was isolated from a nasopharyngeal swab specimen from a female patient in Rabat, Morocco, with coronavirus disease 2019 (COVID-19). This strain belongs to clade 20A and has 12 mutations and 8 amino acid substitutions compared to the reference strain Wuhan/Hu-1/2019.

10.
Hum Vaccin Immunother ; 16(12): 2954-2962, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-32991235

RESUMEN

COVID-19 caused by the virus SARS-CoV-2 has gripped essentially all countries in the world, and has infected millions and killed hundreds of thousands of people. Several innovative approaches are in development to restrain the spread of SARS-CoV-2. In particular, BCG, a vaccine against tuberculosis (TB), is being considered as an alternative therapeutic modality. BCG vaccine is known to induce both humoral and adaptive immunities, thereby activating both nonspecific and cross-reactive immune responses in the host, which combined could effectively resist other pathogens including SARS-CoV-2. Notably, some studies have revealed that SARS-CoV-2 infectivity, case positivity, and mortality rate have been higher in countries that have not adopted BCG vaccination than in countries that have done so. This review presents an overview of the concepts underlying BCG vaccination and its nonspecific immuological effects and protection, resulting in 'trained immunity' and potential utility for resisting COVID-19.


Asunto(s)
Vacuna BCG/uso terapéutico , Vacunas contra la COVID-19/uso terapéutico , COVID-19/prevención & control , Reposicionamiento de Medicamentos/métodos , Inmunidad Adaptativa/efectos de los fármacos , Inmunidad Adaptativa/inmunología , Vacuna BCG/inmunología , Vacuna BCG/farmacología , COVID-19/inmunología , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/farmacología , Reacciones Cruzadas/efectos de los fármacos , Reacciones Cruzadas/inmunología , Humanos , Pandemias , Tuberculosis/inmunología , Tuberculosis/prevención & control
11.
Virus Genes ; 56(5): 582-593, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32651833

RESUMEN

Species A rotaviruses (RVAs) are a leading cause of diarrhea in children and in the young of a large variety of mammalian and avian host species. The purpose of this study was to identify RVA in nomadic goats and calves during severe diarrhea outbreaks in 2012 and 2014 in Bouaarfa, Morocco, and to characterize the complete genomic constellation of two bovine and caprine strains (S18 and S19) and their genetic relatedness with the human strain ma31 detected in 2011 in Morocco. Partial nucleotide sequencing of VP4 and VP7 genes for the twenty-two positive samples revealed three circulating genotypes: G6P[14], G10P[14], and G10P[5] with predominance of G6P[14] genotype. Full-genome sequencing for both strains S18 and S19 presented, respectively, the following genomic constellations: G6-P[14]-I2-R2-C2-M2-A3-N2-T6-E2-H3 and G10-P[14]-I2-R2-C2-M2-A11-N2-T6-E2-H3. Phylogenetic analyses and the analysis of the VP8* antigenic epitopes for S18, S19 and ma31 revealed a shared similarity with bovine, caprine, ovine and human strains from Morocco and other countries. The VP2 and NSP1 genes of the S19 strain were closely related to those of the cognate genes of the human ma31 strain, while the VP4 gene of S18 strain was closely related to the cogent gene of the ma31 strain. Our findings revealed cases of zoonotic transmission and confirmed the risk of emergence of new genotypes in some environments such as nomadic regions, where close physical proximity between human and livestock is common. The present study is novel in reporting whole-genome analyses of RVA isolates obtained from nomadic livestock in Morocco.


Asunto(s)
Infecciones por Rotavirus , Rotavirus , Zoonosis Virales , Animales , Bovinos/virología , Heces/virología , Genoma Viral , Cabras/virología , Humanos , Marruecos/epidemiología , Filogenia , ARN Viral , Proteínas de Unión al ARN/genética , Rotavirus/clasificación , Rotavirus/genética , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/transmisión , Infecciones por Rotavirus/veterinaria , Infecciones por Rotavirus/virología , Proteínas no Estructurales Virales/genética , Zoonosis Virales/epidemiología , Zoonosis Virales/transmisión , Zoonosis Virales/virología
12.
Front Vet Sci ; 7: 606661, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33585597

RESUMEN

The surveillance studies for the presence of caprine rotavirus A (RVA) are limited in India, and the data for the whole-genome analysis of the caprine RVA is not available. This study describes the whole-genome-based analysis of a caprine rotavirus A strain, RVA/Goat-wt/IND/K-98/2015, from a goat kid in India. The genomic analysis revealed that the caprine RVA strain K-98, possess artiodactyl-like and DS-1 human-like genome constellation G8P[1]-I2-R2-C2-M2-A3-N2-T6-E2-H3. The three structural genes (VP2, VP4, and VP7) were close to caprine host having nucleotide-based identity range between 97.5 and 98.9%. Apart from them, other gene segments showed similarity with either bovine or human like genes, ultimately pointing toward a common evolutionary origin having an artiodactyl-type backbone of strain K-98. Phylogenetically, the various genes of the current study isolate also clustered inside clades comprising Human-Bovine-Caprine isolates from worldwide. The current findings add to the knowledge on caprine rotaviruses and might play a substantial role in designing future vaccines or different alternative strategies combating such infections having public health significance. To the best of our knowledge, this is the first report on the whole-genome characterization of a caprine RVA G8P[1] strain from India. Concerning the complex nature of the K-98 genome, whole-genome analyses of more numbers of RVA strains from different parts of the country are needed to comprehend the genomic nature and genetic diversity among caprine RVA.

13.
BMC Infect Dis ; 19(1): 1069, 2019 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-31856744

RESUMEN

BACKGROUND: Tuberculosis represents a serious public health problem and a significant diagnostic and therapeutic challenge worldwide. Molecular diagnostic techniques are crucial in the World Health Organization's new tuberculosis control strategy. This study aims to evaluate the performance of GeneXpert MTB/RIF (Cepheid Sunnyvale, CA, United States) in diagnosis of extra-pulmonary tuberculosis then compare it's performance in detecting Rifampicin resistance to GenoType MTBDRplus (HAIN Life Sciences, Nehren, Germany). METHODS: Samples from pulmonary and/or extra-pulmonary origins were analysed in a 21 months retrospective study. Samples were sent to the bacteriology laboratory for Mycobacterium tuberculosis detection using conventional bacteriological and molecular methods (GeneXpert MTB/RIF and MTBDRplus). Sensitivity and specificity were calculated for the stained smear and GeneXpert according to culture (Gold Standard) as well as for GeneXpert MTB/RIF in both negative and positive microscopy tuberculosis cases. Data's statistical analysis was performed with SPSS13.0 software. RESULTS: Seven hundred fourteen patients' samples were analysed; the average age was 47.21 ± 19.98 years with a male predominance (66.4%). Out of 714 samples: 285 were from pulmonary and 429 were from extra-pulmonary origins. The positivity rates for microscopy, GeneXpert MTB/RIF and culture were 12.88, 20.59 and 15.82%, respectively. These rates were 18.9, 23.85 and 20.35% for pulmonary samples and 9.71, 18.41 and 12.82% for extra-pulmonary samples, respectively. The sensitivity and specificity of GeneXpert MTB/RIF were almost the same in both pulmonary and extra-pulmonary samples (78.2 and 90.4%) and (79,3 and 90.3%) respectively. Rifampicin resistance rate found by GeneXpert MTB/RIF was 0.84%. Comparison of Rifampicin resistance obtained by GeneXpert MTB/RIF and Genotype MTBDRplus, showed 100% agreement between the two techniques for studied samples. CONCLUSIONS: This confirms GeneXpert MTB/RIF advantage for tuberculosis diagnosis, particularly extra-pulmonary tuberculosis with negatively stained smear. The performance of GeneXpert and Genotype MTBDRplus are similar in detection of Rifampicin resistance. However, variability of detection performance according to tuberculosis endemicity deserves more attention in the choice of screening techniques of Rifampicin resistance, hence the interest of conducting comparative studies of detection performance under low and medium endemicity on large samples of tuberculosis populations.


Asunto(s)
Pruebas Diagnósticas de Rutina/métodos , Técnicas de Diagnóstico Molecular/métodos , Mycobacterium tuberculosis/genética , Tuberculosis/diagnóstico , Tuberculosis/epidemiología , Adolescente , Adulto , Anciano , Farmacorresistencia Bacteriana Múltiple , Femenino , Genotipo , Humanos , Incidencia , Masculino , Microscopía , Persona de Mediana Edad , Marruecos/epidemiología , Estudios Retrospectivos , Rifampin/efectos adversos , Rifampin/uso terapéutico , Sensibilidad y Especificidad , Tuberculosis/tratamiento farmacológico , Adulto Joven
14.
Front Microbiol ; 10: 1957, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31608017

RESUMEN

The applications of correct diagnostic approaches play a decisive role in timely containment of infectious diseases spread and mitigation of public health risks. Nevertheless, there is a need to update the diagnostics regularly to capture the new, emergent, and highly divergent viruses. Acute gastroenteritis of viral origin has been identified as a significant cause of mortality across the globe, with the more serious consequences seen at the extremes of age groups (young and elderly) and immune-compromised individuals. Therefore, significant advancements and efforts have been put in the development of enteric virus diagnostics to meet the WHO ASSURED criteria as a benchmark over the years. The Enzyme-Linked Immunosorbent (ELISA) and Polymerase Chain Reaction (PCR) are the basic assays that provided the platform for development of several efficient diagnostics such as real-time RT-PCR, loop-mediated isothermal amplification (LAMP), polymerase spiral reaction (PSR), biosensors, microarrays and next generation sequencing. Herein, we describe and discuss the applications of these advanced technologies in context to enteric virus detection by delineating their features, advantages and limitations.

15.
Virus Genes ; 55(4): 465-478, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31197545

RESUMEN

An unusual group A rotavirus (RVA) strain MAR/ma31/2011/G8P[14] was detected for the first time in Morocco in a stool sample from hospitalized child aged 18 months suffering from acute gastroenteritis and fever in 2011. Complete genome sequencing of the ma31 strain was done using the capillary sequencing technology. The analysis revealed the G8-P[14]-I2-R2-C2-M2-A11-N2-T6-E2-H3 constellation and the backbone genes: I2-R2-C2-M2-A11-N2-T6-E2-H3 are commonly found in RVA strains from artiodactyls such as cattle. The constellation was shared with another Italian zoonotic G8P[14] strains (BA01 and BA02), two Hungarian human strains (182-02 and BP1062) and a sheep RVA strain OVR762. Phylogenetic analysis of each genome segment of ma31 revealed a mixed gene configuration originated from animals and human. Comparison of the antigenic regions of VP7 and VP4 amino acid sequences between ma31 strain and selected animal and human strains bearing G8 and or P[14], showed a high level of conservation, while many substitutions was observed in comparison with RotaTeq™ and Rotarix™ vaccine strains. In contrast, alignment analysis of the four antigenic sites of VP6 revealed a high degree of conservation. These findings reveal a typical zoonotic origin of the strain and confirm a high potential for RVA zoonotic transmission between bovine and humans, allowing the generation of novel rotavirus genotypes.


Asunto(s)
Genoma Viral , Infecciones por Rotavirus/virología , Rotavirus/genética , Zoonosis/virología , Animales , Evolución Molecular , Gastroenteritis/virología , Humanos , Lactante , Masculino , Marruecos , Proteínas de la Nucleocápside/química , Proteínas de la Nucleocápside/genética , Filogenia , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/transmisión , Secuenciación Completa del Genoma , Zoonosis/transmisión
16.
Transbound Emerg Dis ; 66(1): 47-53, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30379411

RESUMEN

Porcine astroviruses (PAstVs) have extended their distribution globally and have a high prevalence; however, their clinical significance is still under investigation. Thus far, information about their prevalence and diversity in the Indian pig population is unknown. This study is the first report on the prevalence and genetic characterization of PAstVs in diarrhoeic piglets in India. From January 2013 to December 2017, 757 samples were screened using an RT-PCR assay and PAstV infection was detected in 17.6% (133/757) pigs. Of the 133 positive samples, 79 (59.4%) were positive for PAstV alone, whereas 54 (40.6%) were found to be co-infected with porcine rotavirus A (PoRVA). Phylogenetic analysis of RdRp/capsid gene region revealed high genetic heterogeneity among PAstV sequences, with a predominance of PAstV lineage 4 and detection of lineage 2. The lineage 4 PAstVs exhibited 61.2%-94.5% sequence similarity at the nucleotide level to other reported sequences, whereas lineage 2 strain shared 66.0%-71.6% sequence identity with cognate sequences of the same lineage. This is the first report on PAstV and circulation of lineages 4 and 2 in India. Further, phylogenetic analysis indicates a multiphyletic origin of PAstV strains and suggests cross-border circulation of PAstVs with a similar genetic configuration in Asian countries.


Asunto(s)
Infecciones por Astroviridae/veterinaria , Diarrea/veterinaria , Mamastrovirus/genética , Enfermedades de los Porcinos/epidemiología , Animales , Infecciones por Astroviridae/epidemiología , Infecciones por Astroviridae/virología , Proteínas de la Cápside/genética , Diarrea/epidemiología , Diarrea/virología , Heces/virología , Variación Genética , Genoma Viral/genética , India/epidemiología , Mamastrovirus/aislamiento & purificación , Prevalencia , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Porcinos , Enfermedades de los Porcinos/virología
17.
BMC Res Notes ; 11(1): 369, 2018 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-29884219

RESUMEN

OBJECTIVE: The integrase strand-transfer inhibitors (INSTIs) are an important class in the arsenal of antiretroviral drugs designed to block the integration of HIV-1 cDNA into the host DNA through the inhibition of DNA strand transfer. In this study for the first time in Morocco, the complete HIV-1 integrase gene was analysed from newly diagnosed patients to evaluate the prevalence of natural polymorphisms and INSTIs resistance-associated mutations in the integrase gene. RESULTS: The 864pb IN coding region was successfully sequenced from plasma sample for 77 among 80 antiretroviral naïve patients. The sequences were interpreted for drug resistance according to the Stanford algorithm. Sixty samples were HIV-1 subtype B (78%), fourteen CRF02_AG (18%), two subtype C and one subtype A. Overall 81 of 288 (28%) amino acid IN positions presented at least one polymorphism each. We found 18 (36.73%), 42 (25.76%) and 21 (27.27%) of polymorphic residues assigned to the N-Terminal Domain, Catalytic Core Domaine and the C-Terminal Domain positions respectively. Primary INSTIs resistance mutation were absent, however secondary mutations L74IM, T97A were detected in four samples (5.2%). These results demonstrate that untreated HIV-1 infected Moroccans will be susceptible to INSTIs.


Asunto(s)
Farmacorresistencia Viral , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Inhibidores de Integrasa VIH/uso terapéutico , VIH-1/fisiología , Adolescente , Adulto , Secuencia de Aminoácidos , Niño , Demografía , Femenino , Humanos , Integrasas/química , Integrasas/genética , Funciones de Verosimilitud , Masculino , Marruecos/epidemiología , Filogenia , Prevalencia , Adulto Joven
18.
Vet Ital ; 54(4): 343-348, 2018 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-30681134

RESUMEN

A  serosurvey  was  conducted  to  determine  the  value  of  camels  (Camelus  dromedaries)  as sentinel animals for the detection of bluetongue virus (BTV) in Morocco. Between 2010 and 2013, camels from various localities in Morocco were randomly tested for antibodies against BTV  serotypes­1,  ­4,  ­6,  ­8,  ­11,  ­14,  and  ­16.  Antibodies  against  1  or  more  serotypes  were detected in 41.8% of 537 camels tested with a competitive enzyme­linked immunosorbent assay  (ELISA)  diagnostic  test.  Of  the  7  tested  serotypes,  only  BTV­11  antibodies  were  not detected with serum neutralisation assays. This study not only confirms the epidemiological presence of BTV­1, ­4, and ­8 in Morocco, but also presents the first evidence of BTV­6, ­14, and ­16 in the country. As such, we conclude that camels would be ideal sentinel animals to determine the potential risk of BTV in Morocco.


Asunto(s)
Virus de la Lengua Azul/aislamiento & purificación , Lengua Azul/epidemiología , Camelus , Especies Centinela/virología , Vigilancia de Guardia/veterinaria , Animales , Lengua Azul/virología , Marruecos/epidemiología , Prevalencia , Medición de Riesgo , Estudios Seroepidemiológicos
19.
BMC Res Notes ; 9: 261, 2016 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-27150259

RESUMEN

BACKGROUND: Group A rotaviruses (RVA) are the main cause of neonatal calve diarrhea (NCD) in Morocco. In this study, we isolated RVA strains from NCD clinical samples in order to support RVA disease control in Morocco. This isolation process constitutes a first step toward vaccine development. METHODS: Thirteen fecal samples were obtained from calves with a single episode of neonate calf diarrhea at three different dairies and two samples were collected from field during a severe NCD outbreak. Diagnosis of RVA infection was based on fecal immune-chromatographic rapid test and further evaluated for their hemagglutination (HA) activity. RVA isolation was carried out on MA104 cells after inoculates were treated with different concentrations of trypsin TPCK. All RVA isolates were confirmed by LSI VetMAX™ Triplex Ruminant Rotavirus & Coronavirus Real-Time PCR kit. G and P typing were determined by direct sequencing of the VP4 and VP7 amplicons. RESULTS: RVA isolation was achieved for nine clinical samples following one or two passages (60 %) and was properly depended on HA activity and trypsin treatment of inoculates. The first sign of CPE detected consisted of increased cell granularity, obscure cell boundaries, cell rounding, and eventual degeneration and detachment of cells. At lower TPCK concentration (3-10 µg/inoculum), no changes at the cellular level were observed, while cells activated with 25-30 µg of trypsin/inoculums, they degenerated and trypsin cytotoxicity was enhanced. Appreciable changes in cell's morphology were detected with optimal trypsin concentration of 15-20 µg trypsin/inoculums. Data from qRT-PCR confirmed that unsuccessful cultivations have No-Ct, and all nine isolates have Ct values ranged between 12.17 and 24.69. Analysis sequencing revealed that field isolates were of G6 P[5] serotype and isolates from the dairy NCD samples were of G10 P[14] serotype. CONCLUSIONS: To our knowledge, this is the first study in Morocco which reports the circulation of G10P[14] in NCD on dairy farms and G6P[5] in the field. Our study constitutes a crucial and a necessary step allowing preventive and veterinary medicine to support RVA disease controls in the country.


Asunto(s)
Animales Recién Nacidos , Diarrea/veterinaria , Infecciones por Rotavirus/veterinaria , Animales , Bovinos , Línea Celular , Diarrea/epidemiología , Diarrea/virología , Humanos , Macaca mulatta , Marruecos/epidemiología , Infecciones por Rotavirus/epidemiología
20.
Avian Pathol ; 44(4): 287-95, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25925561

RESUMEN

The aim of this study was to investigate the prevalence and diversity of infectious bronchitis virus (IBV) genotypes in poultry flocks in 16 areas of Morocco between 2010 and 2014. A total of 360 chicken flocks suspected of being infected by IBV were screened for the IBV N gene using real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Flocks were classified into four groups according to their IBV vaccination programme. Group 1 contained unvaccinated birds. Group 2 received a single application of live H120 vaccine. Groups 3 and 4 birds received one or two booster vaccination(s), respectively, mostly using the H120 vaccine. The real-time RT-PCR results showed that 51.7% of the flocks were positive for the IBV genome with geographical disparities. Molecular characterization of IBV was performed on 50 RT-PCR positive samples by partially sequencing the S1 gene, including the hypervariable regions (nucleotides 705-1097). Two predominant genotypes were detected, with the Massachusetts type dominating (66%), among which 25% of the samples were identical to the H120 vaccine. The second most common genotype (present in 32% of the flocks) was surprisingly Italy 02, revealing the first detection of this genotype in Morocco and also in Africa. 793B, the predominant genotype in the late 1990s in Morocco, was only detected on one occasion and was identical to the 4/91 vaccine strain. This study highlights the high prevalence of IBV in poultry farms in Morocco and confirms its continuous dynamic changes and evolution.


Asunto(s)
Pollos/virología , Infecciones por Coronavirus/veterinaria , Virus de la Bronquitis Infecciosa/inmunología , Enfermedades de las Aves de Corral/epidemiología , Vacunas Virales/inmunología , África/epidemiología , Animales , Secuencia de Bases , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Genotipo , Virus de la Bronquitis Infecciosa/genética , Virus de la Bronquitis Infecciosa/aislamiento & purificación , Italia/epidemiología , Datos de Secuencia Molecular , Marruecos/epidemiología , Filogenia , Enfermedades de las Aves de Corral/virología , Prevalencia , Análisis de Secuencia de ADN/veterinaria , Vacunas Atenuadas/inmunología
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